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Diffstat (limited to 'ecomp-sdk/epsdk-app-overlay/src/main/webapp/app/fusion/external/lodash/4.5.1/lodash.js')
| -rw-r--r-- | ecomp-sdk/epsdk-app-overlay/src/main/webapp/app/fusion/external/lodash/4.5.1/lodash.js | 14932 |
1 files changed, 14932 insertions, 0 deletions
diff --git a/ecomp-sdk/epsdk-app-overlay/src/main/webapp/app/fusion/external/lodash/4.5.1/lodash.js b/ecomp-sdk/epsdk-app-overlay/src/main/webapp/app/fusion/external/lodash/4.5.1/lodash.js new file mode 100644 index 00000000..f1860f12 --- /dev/null +++ b/ecomp-sdk/epsdk-app-overlay/src/main/webapp/app/fusion/external/lodash/4.5.1/lodash.js @@ -0,0 +1,14932 @@ +/** + * @license + * lodash 4.5.1 <https://lodash.com/> + * Copyright 2012-2016 The Dojo Foundation <http://dojofoundation.org/> + * Based on Underscore.js 1.8.3 <http://underscorejs.org/LICENSE> + * Copyright 2009-2016 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors + * Available under MIT license <https://lodash.com/license> + */ +;(function() { + + /** Used as a safe reference for `undefined` in pre-ES5 environments. */ + var undefined; + + /** Used as the semantic version number. */ + var VERSION = '4.5.1'; + + /** Used to compose bitmasks for wrapper metadata. */ + var BIND_FLAG = 1, + BIND_KEY_FLAG = 2, + CURRY_BOUND_FLAG = 4, + CURRY_FLAG = 8, + CURRY_RIGHT_FLAG = 16, + PARTIAL_FLAG = 32, + PARTIAL_RIGHT_FLAG = 64, + ARY_FLAG = 128, + REARG_FLAG = 256, + FLIP_FLAG = 512; + + /** Used to compose bitmasks for comparison styles. */ + var UNORDERED_COMPARE_FLAG = 1, + PARTIAL_COMPARE_FLAG = 2; + + /** Used as default options for `_.truncate`. */ + var DEFAULT_TRUNC_LENGTH = 30, + DEFAULT_TRUNC_OMISSION = '...'; + + /** Used to detect hot functions by number of calls within a span of milliseconds. */ + var HOT_COUNT = 150, + HOT_SPAN = 16; + + /** Used as the size to enable large array optimizations. */ + var LARGE_ARRAY_SIZE = 200; + + /** Used to indicate the type of lazy iteratees. */ + var LAZY_FILTER_FLAG = 1, + LAZY_MAP_FLAG = 2, + LAZY_WHILE_FLAG = 3; + + /** Used as the `TypeError` message for "Functions" methods. */ + var FUNC_ERROR_TEXT = 'Expected a function'; + + /** Used to stand-in for `undefined` hash values. */ + var HASH_UNDEFINED = '__lodash_hash_undefined__'; + + /** Used as references for various `Number` constants. */ + var INFINITY = 1 / 0, + MAX_SAFE_INTEGER = 9007199254740991, + MAX_INTEGER = 1.7976931348623157e+308, + NAN = 0 / 0; + + /** Used as references for the maximum length and index of an array. */ + var MAX_ARRAY_LENGTH = 4294967295, + MAX_ARRAY_INDEX = MAX_ARRAY_LENGTH - 1, + HALF_MAX_ARRAY_LENGTH = MAX_ARRAY_LENGTH >>> 1; + + /** Used as the internal argument placeholder. */ + var PLACEHOLDER = '__lodash_placeholder__'; + + /** `Object#toString` result references. */ + var argsTag = '[object Arguments]', + arrayTag = '[object Array]', + boolTag = '[object Boolean]', + dateTag = '[object Date]', + errorTag = '[object Error]', + funcTag = '[object Function]', + genTag = '[object GeneratorFunction]', + mapTag = '[object Map]', + numberTag = '[object Number]', + objectTag = '[object Object]', + regexpTag = '[object RegExp]', + setTag = '[object Set]', + stringTag = '[object String]', + symbolTag = '[object Symbol]', + weakMapTag = '[object WeakMap]', + weakSetTag = '[object WeakSet]'; + + var arrayBufferTag = '[object ArrayBuffer]', + float32Tag = '[object Float32Array]', + float64Tag = '[object Float64Array]', + int8Tag = '[object Int8Array]', + int16Tag = '[object Int16Array]', + int32Tag = '[object Int32Array]', + uint8Tag = '[object Uint8Array]', + uint8ClampedTag = '[object Uint8ClampedArray]', + uint16Tag = '[object Uint16Array]', + uint32Tag = '[object Uint32Array]'; + + /** Used to match empty string literals in compiled template source. */ + var reEmptyStringLeading = /\b__p \+= '';/g, + reEmptyStringMiddle = /\b(__p \+=) '' \+/g, + reEmptyStringTrailing = /(__e\(.*?\)|\b__t\)) \+\n'';/g; + + /** Used to match HTML entities and HTML characters. */ + var reEscapedHtml = /&(?:amp|lt|gt|quot|#39|#96);/g, + reUnescapedHtml = /[&<>"'`]/g, + reHasEscapedHtml = RegExp(reEscapedHtml.source), + reHasUnescapedHtml = RegExp(reUnescapedHtml.source); + + /** Used to match template delimiters. */ + var reEscape = /<%-([\s\S]+?)%>/g, + reEvaluate = /<%([\s\S]+?)%>/g, + reInterpolate = /<%=([\s\S]+?)%>/g; + + /** Used to match property names within property paths. */ + var reIsDeepProp = /\.|\[(?:[^[\]]*|(["'])(?:(?!\1)[^\\]|\\.)*?\1)\]/, + reIsPlainProp = /^\w*$/, + rePropName = /[^.[\]]+|\[(?:(-?\d+(?:\.\d+)?)|(["'])((?:(?!\2)[^\\]|\\.)*?)\2)\]/g; + + /** Used to match `RegExp` [syntax characters](http://ecma-international.org/ecma-262/6.0/#sec-patterns). */ + var reRegExpChar = /[\\^$.*+?()[\]{}|]/g, + reHasRegExpChar = RegExp(reRegExpChar.source); + + /** Used to match leading and trailing whitespace. */ + var reTrim = /^\s+|\s+$/g, + reTrimStart = /^\s+/, + reTrimEnd = /\s+$/; + + /** Used to match backslashes in property paths. */ + var reEscapeChar = /\\(\\)?/g; + + /** Used to match [ES template delimiters](http://ecma-international.org/ecma-262/6.0/#sec-template-literal-lexical-components). */ + var reEsTemplate = /\$\{([^\\}]*(?:\\.[^\\}]*)*)\}/g; + + /** Used to match `RegExp` flags from their coerced string values. */ + var reFlags = /\w*$/; + + /** Used to detect hexadecimal string values. */ + var reHasHexPrefix = /^0x/i; + + /** Used to detect bad signed hexadecimal string values. */ + var reIsBadHex = /^[-+]0x[0-9a-f]+$/i; + + /** Used to detect binary string values. */ + var reIsBinary = /^0b[01]+$/i; + + /** Used to detect host constructors (Safari > 5). */ + var reIsHostCtor = /^\[object .+?Constructor\]$/; + + /** Used to detect octal string values. */ + var reIsOctal = /^0o[0-7]+$/i; + + /** Used to detect unsigned integer values. */ + var reIsUint = /^(?:0|[1-9]\d*)$/; + + /** Used to match latin-1 supplementary letters (excluding mathematical operators). */ + var reLatin1 = /[\xc0-\xd6\xd8-\xde\xdf-\xf6\xf8-\xff]/g; + + /** Used to ensure capturing order of template delimiters. */ + var reNoMatch = /($^)/; + + /** Used to match unescaped characters in compiled string literals. */ + var reUnescapedString = /['\n\r\u2028\u2029\\]/g; + + /** Used to compose unicode character classes. */ + var rsAstralRange = '\\ud800-\\udfff', + rsComboMarksRange = '\\u0300-\\u036f\\ufe20-\\ufe23', + rsComboSymbolsRange = '\\u20d0-\\u20f0', + rsDingbatRange = '\\u2700-\\u27bf', + rsLowerRange = 'a-z\\xdf-\\xf6\\xf8-\\xff', + rsMathOpRange = '\\xac\\xb1\\xd7\\xf7', + rsNonCharRange = '\\x00-\\x2f\\x3a-\\x40\\x5b-\\x60\\x7b-\\xbf', + rsQuoteRange = '\\u2018\\u2019\\u201c\\u201d', + rsSpaceRange = ' \\t\\x0b\\f\\xa0\\ufeff\\n\\r\\u2028\\u2029\\u1680\\u180e\\u2000\\u2001\\u2002\\u2003\\u2004\\u2005\\u2006\\u2007\\u2008\\u2009\\u200a\\u202f\\u205f\\u3000', + rsUpperRange = 'A-Z\\xc0-\\xd6\\xd8-\\xde', + rsVarRange = '\\ufe0e\\ufe0f', + rsBreakRange = rsMathOpRange + rsNonCharRange + rsQuoteRange + rsSpaceRange; + + /** Used to compose unicode capture groups. */ + var rsAstral = '[' + rsAstralRange + ']', + rsBreak = '[' + rsBreakRange + ']', + rsCombo = '[' + rsComboMarksRange + rsComboSymbolsRange + ']', + rsDigits = '\\d+', + rsDingbat = '[' + rsDingbatRange + ']', + rsLower = '[' + rsLowerRange + ']', + rsMisc = '[^' + rsAstralRange + rsBreakRange + rsDigits + rsDingbatRange + rsLowerRange + rsUpperRange + ']', + rsFitz = '\\ud83c[\\udffb-\\udfff]', + rsModifier = '(?:' + rsCombo + '|' + rsFitz + ')', + rsNonAstral = '[^' + rsAstralRange + ']', + rsRegional = '(?:\\ud83c[\\udde6-\\uddff]){2}', + rsSurrPair = '[\\ud800-\\udbff][\\udc00-\\udfff]', + rsUpper = '[' + rsUpperRange + ']', + rsZWJ = '\\u200d'; + + /** Used to compose unicode regexes. */ + var rsLowerMisc = '(?:' + rsLower + '|' + rsMisc + ')', + rsUpperMisc = '(?:' + rsUpper + '|' + rsMisc + ')', + reOptMod = rsModifier + '?', + rsOptVar = '[' + rsVarRange + ']?', + rsOptJoin = '(?:' + rsZWJ + '(?:' + [rsNonAstral, rsRegional, rsSurrPair].join('|') + ')' + rsOptVar + reOptMod + ')*', + rsSeq = rsOptVar + reOptMod + rsOptJoin, + rsEmoji = '(?:' + [rsDingbat, rsRegional, rsSurrPair].join('|') + ')' + rsSeq, + rsSymbol = '(?:' + [rsNonAstral + rsCombo + '?', rsCombo, rsRegional, rsSurrPair, rsAstral].join('|') + ')'; + + /** + * Used to match [combining diacritical marks](https://en.wikipedia.org/wiki/Combining_Diacritical_Marks) and + * [combining diacritical marks for symbols](https://en.wikipedia.org/wiki/Combining_Diacritical_Marks_for_Symbols). + */ + var reComboMark = RegExp(rsCombo, 'g'); + + /** Used to match [string symbols](https://mathiasbynens.be/notes/javascript-unicode). */ + var reComplexSymbol = RegExp(rsFitz + '(?=' + rsFitz + ')|' + rsSymbol + rsSeq, 'g'); + + /** Used to detect strings with [zero-width joiners or code points from the astral planes](http://eev.ee/blog/2015/09/12/dark-corners-of-unicode/). */ + var reHasComplexSymbol = RegExp('[' + rsZWJ + rsAstralRange + rsComboMarksRange + rsComboSymbolsRange + rsVarRange + ']'); + + /** Used to match non-compound words composed of alphanumeric characters. */ + var reBasicWord = /[a-zA-Z0-9]+/g; + + /** Used to match complex or compound words. */ + var reComplexWord = RegExp([ + rsUpper + '?' + rsLower + '+(?=' + [rsBreak, rsUpper, '$'].join('|') + ')', + rsUpperMisc + '+(?=' + [rsBreak, rsUpper + rsLowerMisc, '$'].join('|') + ')', + rsUpper + '?' + rsLowerMisc + '+', + rsUpper + '+', + rsDigits, + rsEmoji + ].join('|'), 'g'); + + /** Used to detect strings that need a more robust regexp to match words. */ + var reHasComplexWord = /[a-z][A-Z]|[0-9][a-zA-Z]|[a-zA-Z][0-9]|[^a-zA-Z0-9 ]/; + + /** Used to assign default `context` object properties. */ + var contextProps = [ + 'Array', 'Buffer', 'Date', 'Error', 'Float32Array', 'Float64Array', + 'Function', 'Int8Array', 'Int16Array', 'Int32Array', 'Map', 'Math', 'Object', + 'Reflect', 'RegExp', 'Set', 'String', 'Symbol', 'TypeError', 'Uint8Array', + 'Uint8ClampedArray', 'Uint16Array', 'Uint32Array', 'WeakMap', '_', + 'clearTimeout', 'isFinite', 'parseInt', 'setTimeout' + ]; + + /** Used to make template sourceURLs easier to identify. */ + var templateCounter = -1; + + /** Used to identify `toStringTag` values of typed arrays. */ + var typedArrayTags = {}; + typedArrayTags[float32Tag] = typedArrayTags[float64Tag] = + typedArrayTags[int8Tag] = typedArrayTags[int16Tag] = + typedArrayTags[int32Tag] = typedArrayTags[uint8Tag] = + typedArrayTags[uint8ClampedTag] = typedArrayTags[uint16Tag] = + typedArrayTags[uint32Tag] = true; + typedArrayTags[argsTag] = typedArrayTags[arrayTag] = + typedArrayTags[arrayBufferTag] = typedArrayTags[boolTag] = + typedArrayTags[dateTag] = typedArrayTags[errorTag] = + typedArrayTags[funcTag] = typedArrayTags[mapTag] = + typedArrayTags[numberTag] = typedArrayTags[objectTag] = + typedArrayTags[regexpTag] = typedArrayTags[setTag] = + typedArrayTags[stringTag] = typedArrayTags[weakMapTag] = false; + + /** Used to identify `toStringTag` values supported by `_.clone`. */ + var cloneableTags = {}; + cloneableTags[argsTag] = cloneableTags[arrayTag] = + cloneableTags[arrayBufferTag] = cloneableTags[boolTag] = + cloneableTags[dateTag] = cloneableTags[float32Tag] = + cloneableTags[float64Tag] = cloneableTags[int8Tag] = + cloneableTags[int16Tag] = cloneableTags[int32Tag] = + cloneableTags[mapTag] = cloneableTags[numberTag] = + cloneableTags[objectTag] = cloneableTags[regexpTag] = + cloneableTags[setTag] = cloneableTags[stringTag] = + cloneableTags[symbolTag] = cloneableTags[uint8Tag] = + cloneableTags[uint8ClampedTag] = cloneableTags[uint16Tag] = + cloneableTags[uint32Tag] = true; + cloneableTags[errorTag] = cloneableTags[funcTag] = + cloneableTags[weakMapTag] = false; + + /** Used to map latin-1 supplementary letters to basic latin letters. */ + var deburredLetters = { + '\xc0': 'A', '\xc1': 'A', '\xc2': 'A', '\xc3': 'A', '\xc4': 'A', '\xc5': 'A', + '\xe0': 'a', '\xe1': 'a', '\xe2': 'a', '\xe3': 'a', '\xe4': 'a', '\xe5': 'a', + '\xc7': 'C', '\xe7': 'c', + '\xd0': 'D', '\xf0': 'd', + '\xc8': 'E', '\xc9': 'E', '\xca': 'E', '\xcb': 'E', + '\xe8': 'e', '\xe9': 'e', '\xea': 'e', '\xeb': 'e', + '\xcC': 'I', '\xcd': 'I', '\xce': 'I', '\xcf': 'I', + '\xeC': 'i', '\xed': 'i', '\xee': 'i', '\xef': 'i', + '\xd1': 'N', '\xf1': 'n', + '\xd2': 'O', '\xd3': 'O', '\xd4': 'O', '\xd5': 'O', '\xd6': 'O', '\xd8': 'O', + '\xf2': 'o', '\xf3': 'o', '\xf4': 'o', '\xf5': 'o', '\xf6': 'o', '\xf8': 'o', + '\xd9': 'U', '\xda': 'U', '\xdb': 'U', '\xdc': 'U', + '\xf9': 'u', '\xfa': 'u', '\xfb': 'u', '\xfc': 'u', + '\xdd': 'Y', '\xfd': 'y', '\xff': 'y', + '\xc6': 'Ae', '\xe6': 'ae', + '\xde': 'Th', '\xfe': 'th', + '\xdf': 'ss' + }; + + /** Used to map characters to HTML entities. */ + var htmlEscapes = { + '&': '&', + '<': '<', + '>': '>', + '"': '"', + "'": ''', + '`': '`' + }; + + /** Used to map HTML entities to characters. */ + var htmlUnescapes = { + '&': '&', + '<': '<', + '>': '>', + '"': '"', + ''': "'", + '`': '`' + }; + + /** Used to determine if values are of the language type `Object`. */ + var objectTypes = { + 'function': true, + 'object': true + }; + + /** Used to escape characters for inclusion in compiled string literals. */ + var stringEscapes = { + '\\': '\\', + "'": "'", + '\n': 'n', + '\r': 'r', + '\u2028': 'u2028', + '\u2029': 'u2029' + }; + + /** Built-in method references without a dependency on `root`. */ + var freeParseFloat = parseFloat, + freeParseInt = parseInt; + + /** Detect free variable `exports`. */ + var freeExports = (objectTypes[typeof exports] && exports && !exports.nodeType) + ? exports + : undefined; + + /** Detect free variable `module`. */ + var freeModule = (objectTypes[typeof module] && module && !module.nodeType) + ? module + : undefined; + + /** Detect the popular CommonJS extension `module.exports`. */ + var moduleExports = (freeModule && freeModule.exports === freeExports) + ? freeExports + : undefined; + + /** Detect free variable `global` from Node.js. */ + var freeGlobal = checkGlobal(freeExports && freeModule && typeof global == 'object' && global); + + /** Detect free variable `self`. */ + var freeSelf = checkGlobal(objectTypes[typeof self] && self); + + /** Detect free variable `window`. */ + var freeWindow = checkGlobal(objectTypes[typeof window] && window); + + /** Detect `this` as the global object. */ + var thisGlobal = checkGlobal(objectTypes[typeof this] && this); + + /** + * Used as a reference to the global object. + * + * The `this` value is used if it's the global object to avoid Greasemonkey's + * restricted `window` object, otherwise the `window` object is used. + */ + var root = freeGlobal || + ((freeWindow !== (thisGlobal && thisGlobal.window)) && freeWindow) || + freeSelf || thisGlobal || Function('return this')(); + + /*--------------------------------------------------------------------------*/ + + /** + * Adds the key-value `pair` to `map`. + * + * @private + * @param {Object} map The map to modify. + * @param {Array} pair The key-value pair to add. + * @returns {Object} Returns `map`. + */ + function addMapEntry(map, pair) { + map.set(pair[0], pair[1]); + return map; + } + + /** + * Adds `value` to `set`. + * + * @private + * @param {Object} set The set to modify. + * @param {*} value The value to add. + * @returns {Object} Returns `set`. + */ + function addSetEntry(set, value) { + set.add(value); + return set; + } + + /** + * A faster alternative to `Function#apply`, this function invokes `func` + * with the `this` binding of `thisArg` and the arguments of `args`. + * + * @private + * @param {Function} func The function to invoke. + * @param {*} thisArg The `this` binding of `func`. + * @param {...*} args The arguments to invoke `func` with. + * @returns {*} Returns the result of `func`. + */ + function apply(func, thisArg, args) { + var length = args.length; + switch (length) { + case 0: return func.call(thisArg); + case 1: return func.call(thisArg, args[0]); + case 2: return func.call(thisArg, args[0], args[1]); + case 3: return func.call(thisArg, args[0], args[1], args[2]); + } + return func.apply(thisArg, args); + } + + /** + * A specialized version of `baseAggregator` for arrays. + * + * @private + * @param {Array} array The array to iterate over. + * @param {Function} setter The function to set `accumulator` values. + * @param {Function} iteratee The iteratee to transform keys. + * @param {Object} accumulator The initial aggregated object. + * @returns {Function} Returns `accumulator`. + */ + function arrayAggregator(array, setter, iteratee, accumulator) { + var index = -1, + length = array.length; + + while (++index < length) { + var value = array[index]; + setter(accumulator, value, iteratee(value), array); + } + return accumulator; + } + + /** + * Creates a new array concatenating `array` with `other`. + * + * @private + * @param {Array} array The first array to concatenate. + * @param {Array} other The second array to concatenate. + * @returns {Array} Returns the new concatenated array. + */ + function arrayConcat(array, other) { + var index = -1, + length = array.length, + othIndex = -1, + othLength = other.length, + result = Array(length + othLength); + + while (++index < length) { + result[index] = array[index]; + } + while (++othIndex < othLength) { + result[index++] = other[othIndex]; + } + return result; + } + + /** + * A specialized version of `_.forEach` for arrays without support for + * iteratee shorthands. + * + * @private + * @param {Array} array The array to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @returns {Array} Returns `array`. + */ + function arrayEach(array, iteratee) { + var index = -1, + length = array.length; + + while (++index < length) { + if (iteratee(array[index], index, array) === false) { + break; + } + } + return array; + } + + /** + * A specialized version of `_.forEachRight` for arrays without support for + * iteratee shorthands. + * + * @private + * @param {Array} array The array to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @returns {Array} Returns `array`. + */ + function arrayEachRight(array, iteratee) { + var length = array.length; + + while (length--) { + if (iteratee(array[length], length, array) === false) { + break; + } + } + return array; + } + + /** + * A specialized version of `_.every` for arrays without support for + * iteratee shorthands. + * + * @private + * @param {Array} array The array to iterate over. + * @param {Function} predicate The function invoked per iteration. + * @returns {boolean} Returns `true` if all elements pass the predicate check, else `false`. + */ + function arrayEvery(array, predicate) { + var index = -1, + length = array.length; + + while (++index < length) { + if (!predicate(array[index], index, array)) { + return false; + } + } + return true; + } + + /** + * A specialized version of `_.filter` for arrays without support for + * iteratee shorthands. + * + * @private + * @param {Array} array The array to iterate over. + * @param {Function} predicate The function invoked per iteration. + * @returns {Array} Returns the new filtered array. + */ + function arrayFilter(array, predicate) { + var index = -1, + length = array.length, + resIndex = -1, + result = []; + + while (++index < length) { + var value = array[index]; + if (predicate(value, index, array)) { + result[++resIndex] = value; + } + } + return result; + } + + /** + * A specialized version of `_.includes` for arrays without support for + * specifying an index to search from. + * + * @private + * @param {Array} array The array to search. + * @param {*} target The value to search for. + * @returns {boolean} Returns `true` if `target` is found, else `false`. + */ + function arrayIncludes(array, value) { + return !!array.length && baseIndexOf(array, value, 0) > -1; + } + + /** + * A specialized version of `_.includesWith` for arrays without support for + * specifying an index to search from. + * + * @private + * @param {Array} array The array to search. + * @param {*} target The value to search for. + * @param {Function} comparator The comparator invoked per element. + * @returns {boolean} Returns `true` if `target` is found, else `false`. + */ + function arrayIncludesWith(array, value, comparator) { + var index = -1, + length = array.length; + + while (++index < length) { + if (comparator(value, array[index])) { + return true; + } + } + return false; + } + + /** + * A specialized version of `_.map` for arrays without support for iteratee + * shorthands. + * + * @private + * @param {Array} array The array to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @returns {Array} Returns the new mapped array. + */ + function arrayMap(array, iteratee) { + var index = -1, + length = array.length, + result = Array(length); + + while (++index < length) { + result[index] = iteratee(array[index], index, array); + } + return result; + } + + /** + * Appends the elements of `values` to `array`. + * + * @private + * @param {Array} array The array to modify. + * @param {Array} values The values to append. + * @returns {Array} Returns `array`. + */ + function arrayPush(array, values) { + var index = -1, + length = values.length, + offset = array.length; + + while (++index < length) { + array[offset + index] = values[index]; + } + return array; + } + + /** + * A specialized version of `_.reduce` for arrays without support for + * iteratee shorthands. + * + * @private + * @param {Array} array The array to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @param {*} [accumulator] The initial value. + * @param {boolean} [initAccum] Specify using the first element of `array` as the initial value. + * @returns {*} Returns the accumulated value. + */ + function arrayReduce(array, iteratee, accumulator, initAccum) { + var index = -1, + length = array.length; + + if (initAccum && length) { + accumulator = array[++index]; + } + while (++index < length) { + accumulator = iteratee(accumulator, array[index], index, array); + } + return accumulator; + } + + /** + * A specialized version of `_.reduceRight` for arrays without support for + * iteratee shorthands. + * + * @private + * @param {Array} array The array to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @param {*} [accumulator] The initial value. + * @param {boolean} [initAccum] Specify using the last element of `array` as the initial value. + * @returns {*} Returns the accumulated value. + */ + function arrayReduceRight(array, iteratee, accumulator, initAccum) { + var length = array.length; + if (initAccum && length) { + accumulator = array[--length]; + } + while (length--) { + accumulator = iteratee(accumulator, array[length], length, array); + } + return accumulator; + } + + /** + * A specialized version of `_.some` for arrays without support for iteratee + * shorthands. + * + * @private + * @param {Array} array The array to iterate over. + * @param {Function} predicate The function invoked per iteration. + * @returns {boolean} Returns `true` if any element passes the predicate check, else `false`. + */ + function arraySome(array, predicate) { + var index = -1, + length = array.length; + + while (++index < length) { + if (predicate(array[index], index, array)) { + return true; + } + } + return false; + } + + /** + * The base implementation of methods like `_.max` and `_.min` which accepts a + * `comparator` to determine the extremum value. + * + * @private + * @param {Array} array The array to iterate over. + * @param {Function} iteratee The iteratee invoked per iteration. + * @param {Function} comparator The comparator used to compare values. + * @returns {*} Returns the extremum value. + */ + function baseExtremum(array, iteratee, comparator) { + var index = -1, + length = array.length; + + while (++index < length) { + var value = array[index], + current = iteratee(value); + + if (current != null && (computed === undefined + ? current === current + : comparator(current, computed) + )) { + var computed = current, + result = value; + } + } + return result; + } + + /** + * The base implementation of methods like `_.find` and `_.findKey`, without + * support for iteratee shorthands, which iterates over `collection` using + * `eachFunc`. + * + * @private + * @param {Array|Object} collection The collection to search. + * @param {Function} predicate The function invoked per iteration. + * @param {Function} eachFunc The function to iterate over `collection`. + * @param {boolean} [retKey] Specify returning the key of the found element instead of the element itself. + * @returns {*} Returns the found element or its key, else `undefined`. + */ + function baseFind(collection, predicate, eachFunc, retKey) { + var result; + eachFunc(collection, function(value, key, collection) { + if (predicate(value, key, collection)) { + result = retKey ? key : value; + return false; + } + }); + return result; + } + + /** + * The base implementation of `_.findIndex` and `_.findLastIndex` without + * support for iteratee shorthands. + * + * @private + * @param {Array} array The array to search. + * @param {Function} predicate The function invoked per iteration. + * @param {boolean} [fromRight] Specify iterating from right to left. + * @returns {number} Returns the index of the matched value, else `-1`. + */ + function baseFindIndex(array, predicate, fromRight) { + var length = array.length, + index = fromRight ? length : -1; + + while ((fromRight ? index-- : ++index < length)) { + if (predicate(array[index], index, array)) { + return index; + } + } + return -1; + } + + /** + * The base implementation of `_.indexOf` without `fromIndex` bounds checks. + * + * @private + * @param {Array} array The array to search. + * @param {*} value The value to search for. + * @param {number} fromIndex The index to search from. + * @returns {number} Returns the index of the matched value, else `-1`. + */ + function baseIndexOf(array, value, fromIndex) { + if (value !== value) { + return indexOfNaN(array, fromIndex); + } + var index = fromIndex - 1, + length = array.length; + + while (++index < length) { + if (array[index] === value) { + return index; + } + } + return -1; + } + + /** + * The base implementation of `_.reduce` and `_.reduceRight`, without support + * for iteratee shorthands, which iterates over `collection` using `eachFunc`. + * + * @private + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @param {*} accumulator The initial value. + * @param {boolean} initAccum Specify using the first or last element of `collection` as the initial value. + * @param {Function} eachFunc The function to iterate over `collection`. + * @returns {*} Returns the accumulated value. + */ + function baseReduce(collection, iteratee, accumulator, initAccum, eachFunc) { + eachFunc(collection, function(value, index, collection) { + accumulator = initAccum + ? (initAccum = false, value) + : iteratee(accumulator, value, index, collection); + }); + return accumulator; + } + + /** + * The base implementation of `_.sortBy` which uses `comparer` to define + * the sort order of `array` and replaces criteria objects with their + * corresponding values. + * + * @private + * @param {Array} array The array to sort. + * @param {Function} comparer The function to define sort order. + * @returns {Array} Returns `array`. + */ + function baseSortBy(array, comparer) { + var length = array.length; + + array.sort(comparer); + while (length--) { + array[length] = array[length].value; + } + return array; + } + + /** + * The base implementation of `_.sum` without support for iteratee shorthands. + * + * @private + * @param {Array} array The array to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @returns {number} Returns the sum. + */ + function baseSum(array, iteratee) { + var result, + index = -1, + length = array.length; + + while (++index < length) { + var current = iteratee(array[index]); + if (current !== undefined) { + result = result === undefined ? current : (result + current); + } + } + return result; + } + + /** + * The base implementation of `_.times` without support for iteratee shorthands + * or max array length checks. + * + * @private + * @param {number} n The number of times to invoke `iteratee`. + * @param {Function} iteratee The function invoked per iteration. + * @returns {Array} Returns the array of results. + */ + function baseTimes(n, iteratee) { + var index = -1, + result = Array(n); + + while (++index < n) { + result[index] = iteratee(index); + } + return result; + } + + /** + * The base implementation of `_.toPairs` and `_.toPairsIn` which creates an array + * of key-value pairs for `object` corresponding to the property names of `props`. + * + * @private + * @param {Object} object The object to query. + * @param {Array} props The property names to get values for. + * @returns {Object} Returns the new array of key-value pairs. + */ + function baseToPairs(object, props) { + return arrayMap(props, function(key) { + return [key, object[key]]; + }); + } + + /** + * The base implementation of `_.unary` without support for storing wrapper metadata. + * + * @private + * @param {Function} func The function to cap arguments for. + * @returns {Function} Returns the new function. + */ + function baseUnary(func) { + return function(value) { + return func(value); + }; + } + + /** + * The base implementation of `_.values` and `_.valuesIn` which creates an + * array of `object` property values corresponding to the property names + * of `props`. + * + * @private + * @param {Object} object The object to query. + * @param {Array} props The property names to get values for. + * @returns {Object} Returns the array of property values. + */ + function baseValues(object, props) { + return arrayMap(props, function(key) { + return object[key]; + }); + } + + /** + * Used by `_.trim` and `_.trimStart` to get the index of the first string symbol + * that is not found in the character symbols. + * + * @private + * @param {Array} strSymbols The string symbols to inspect. + * @param {Array} chrSymbols The character symbols to find. + * @returns {number} Returns the index of the first unmatched string symbol. + */ + function charsStartIndex(strSymbols, chrSymbols) { + var index = -1, + length = strSymbols.length; + + while (++index < length && baseIndexOf(chrSymbols, strSymbols[index], 0) > -1) {} + return index; + } + + /** + * Used by `_.trim` and `_.trimEnd` to get the index of the last string symbol + * that is not found in the character symbols. + * + * @private + * @param {Array} strSymbols The string symbols to inspect. + * @param {Array} chrSymbols The character symbols to find. + * @returns {number} Returns the index of the last unmatched string symbol. + */ + function charsEndIndex(strSymbols, chrSymbols) { + var index = strSymbols.length; + + while (index-- && baseIndexOf(chrSymbols, strSymbols[index], 0) > -1) {} + return index; + } + + /** + * Checks if `value` is a global object. + * + * @private + * @param {*} value The value to check. + * @returns {null|Object} Returns `value` if it's a global object, else `null`. + */ + function checkGlobal(value) { + return (value && value.Object === Object) ? value : null; + } + + /** + * Compares values to sort them in ascending order. + * + * @private + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @returns {number} Returns the sort order indicator for `value`. + */ + function compareAscending(value, other) { + if (value !== other) { + var valIsNull = value === null, + valIsUndef = value === undefined, + valIsReflexive = value === value; + + var othIsNull = other === null, + othIsUndef = other === undefined, + othIsReflexive = other === other; + + if ((value > other && !othIsNull) || !valIsReflexive || + (valIsNull && !othIsUndef && othIsReflexive) || + (valIsUndef && othIsReflexive)) { + return 1; + } + if ((value < other && !valIsNull) || !othIsReflexive || + (othIsNull && !valIsUndef && valIsReflexive) || + (othIsUndef && valIsReflexive)) { + return -1; + } + } + return 0; + } + + /** + * Used by `_.orderBy` to compare multiple properties of a value to another + * and stable sort them. + * + * If `orders` is unspecified, all values are sorted in ascending order. Otherwise, + * specify an order of "desc" for descending or "asc" for ascending sort order + * of corresponding values. + * + * @private + * @param {Object} object The object to compare. + * @param {Object} other The other object to compare. + * @param {boolean[]|string[]} orders The order to sort by for each property. + * @returns {number} Returns the sort order indicator for `object`. + */ + function compareMultiple(object, other, orders) { + var index = -1, + objCriteria = object.criteria, + othCriteria = other.criteria, + length = objCriteria.length, + ordersLength = orders.length; + + while (++index < length) { + var result = compareAscending(objCriteria[index], othCriteria[index]); + if (result) { + if (index >= ordersLength) { + return result; + } + var order = orders[index]; + return result * (order == 'desc' ? -1 : 1); + } + } + // Fixes an `Array#sort` bug in the JS engine embedded in Adobe applications + // that causes it, under certain circumstances, to provide the same value for + // `object` and `other`. See https://github.com/jashkenas/underscore/pull/1247 + // for more details. + // + // This also ensures a stable sort in V8 and other engines. + // See https://code.google.com/p/v8/issues/detail?id=90 for more details. + return object.index - other.index; + } + + /** + * Gets the number of `placeholder` occurrences in `array`. + * + * @private + * @param {Array} array The array to inspect. + * @param {*} placeholder The placeholder to search for. + * @returns {number} Returns the placeholder count. + */ + function countHolders(array, placeholder) { + var length = array.length, + result = 0; + + while (length--) { + if (array[length] === placeholder) { + result++; + } + } + return result; + } + + /** + * Used by `_.deburr` to convert latin-1 supplementary letters to basic latin letters. + * + * @private + * @param {string} letter The matched letter to deburr. + * @returns {string} Returns the deburred letter. + */ + function deburrLetter(letter) { + return deburredLetters[letter]; + } + + /** + * Used by `_.escape` to convert characters to HTML entities. + * + * @private + * @param {string} chr The matched character to escape. + * @returns {string} Returns the escaped character. + */ + function escapeHtmlChar(chr) { + return htmlEscapes[chr]; + } + + /** + * Used by `_.template` to escape characters for inclusion in compiled string literals. + * + * @private + * @param {string} chr The matched character to escape. + * @returns {string} Returns the escaped character. + */ + function escapeStringChar(chr) { + return '\\' + stringEscapes[chr]; + } + + /** + * Gets the index at which the first occurrence of `NaN` is found in `array`. + * + * @private + * @param {Array} array The array to search. + * @param {number} fromIndex The index to search from. + * @param {boolean} [fromRight] Specify iterating from right to left. + * @returns {number} Returns the index of the matched `NaN`, else `-1`. + */ + function indexOfNaN(array, fromIndex, fromRight) { + var length = array.length, + index = fromIndex + (fromRight ? 0 : -1); + + while ((fromRight ? index-- : ++index < length)) { + var other = array[index]; + if (other !== other) { + return index; + } + } + return -1; + } + + /** + * Checks if `value` is a host object in IE < 9. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a host object, else `false`. + */ + function isHostObject(value) { + // Many host objects are `Object` objects that can coerce to strings + // despite having improperly defined `toString` methods. + var result = false; + if (value != null && typeof value.toString != 'function') { + try { + result = !!(value + ''); + } catch (e) {} + } + return result; + } + + /** + * Checks if `value` is a valid array-like index. + * + * @private + * @param {*} value The value to check. + * @param {number} [length=MAX_SAFE_INTEGER] The upper bounds of a valid index. + * @returns {boolean} Returns `true` if `value` is a valid index, else `false`. + */ + function isIndex(value, length) { + value = (typeof value == 'number' || reIsUint.test(value)) ? +value : -1; + length = length == null ? MAX_SAFE_INTEGER : length; + return value > -1 && value % 1 == 0 && value < length; + } + + /** + * Converts `iterator` to an array. + * + * @private + * @param {Object} iterator The iterator to convert. + * @returns {Array} Returns the converted array. + */ + function iteratorToArray(iterator) { + var data, + result = []; + + while (!(data = iterator.next()).done) { + result.push(data.value); + } + return result; + } + + /** + * Converts `map` to an array. + * + * @private + * @param {Object} map The map to convert. + * @returns {Array} Returns the converted array. + */ + function mapToArray(map) { + var index = -1, + result = Array(map.size); + + map.forEach(function(value, key) { + result[++index] = [key, value]; + }); + return result; + } + + /** + * Replaces all `placeholder` elements in `array` with an internal placeholder + * and returns an array of their indexes. + * + * @private + * @param {Array} array The array to modify. + * @param {*} placeholder The placeholder to replace. + * @returns {Array} Returns the new array of placeholder indexes. + */ + function replaceHolders(array, placeholder) { + var index = -1, + length = array.length, + resIndex = -1, + result = []; + + while (++index < length) { + var value = array[index]; + if (value === placeholder || value === PLACEHOLDER) { + array[index] = PLACEHOLDER; + result[++resIndex] = index; + } + } + return result; + } + + /** + * Converts `set` to an array. + * + * @private + * @param {Object} set The set to convert. + * @returns {Array} Returns the converted array. + */ + function setToArray(set) { + var index = -1, + result = Array(set.size); + + set.forEach(function(value) { + result[++index] = value; + }); + return result; + } + + /** + * Gets the number of symbols in `string`. + * + * @private + * @param {string} string The string to inspect. + * @returns {number} Returns the string size. + */ + function stringSize(string) { + if (!(string && reHasComplexSymbol.test(string))) { + return string.length; + } + var result = reComplexSymbol.lastIndex = 0; + while (reComplexSymbol.test(string)) { + result++; + } + return result; + } + + /** + * Converts `string` to an array. + * + * @private + * @param {string} string The string to convert. + * @returns {Array} Returns the converted array. + */ + function stringToArray(string) { + return string.match(reComplexSymbol); + } + + /** + * Used by `_.unescape` to convert HTML entities to characters. + * + * @private + * @param {string} chr The matched character to unescape. + * @returns {string} Returns the unescaped character. + */ + function unescapeHtmlChar(chr) { + return htmlUnescapes[chr]; + } + + /*--------------------------------------------------------------------------*/ + + /** + * Create a new pristine `lodash` function using the `context` object. + * + * @static + * @memberOf _ + * @category Util + * @param {Object} [context=root] The context object. + * @returns {Function} Returns a new `lodash` function. + * @example + * + * _.mixin({ 'foo': _.constant('foo') }); + * + * var lodash = _.runInContext(); + * lodash.mixin({ 'bar': lodash.constant('bar') }); + * + * _.isFunction(_.foo); + * // => true + * _.isFunction(_.bar); + * // => false + * + * lodash.isFunction(lodash.foo); + * // => false + * lodash.isFunction(lodash.bar); + * // => true + * + * // Use `context` to mock `Date#getTime` use in `_.now`. + * var mock = _.runInContext({ + * 'Date': function() { + * return { 'getTime': getTimeMock }; + * } + * }); + * + * // Create a suped-up `defer` in Node.js. + * var defer = _.runInContext({ 'setTimeout': setImmediate }).defer; + */ + function runInContext(context) { + context = context ? _.defaults({}, context, _.pick(root, contextProps)) : root; + + /** Built-in constructor references. */ + var Date = context.Date, + Error = context.Error, + Math = context.Math, + RegExp = context.RegExp, + TypeError = context.TypeError; + + /** Used for built-in method references. */ + var arrayProto = context.Array.prototype, + objectProto = context.Object.prototype; + + /** Used to resolve the decompiled source of functions. */ + var funcToString = context.Function.prototype.toString; + + /** Used to check objects for own properties. */ + var hasOwnProperty = objectProto.hasOwnProperty; + + /** Used to generate unique IDs. */ + var idCounter = 0; + + /** Used to infer the `Object` constructor. */ + var objectCtorString = funcToString.call(Object); + + /** + * Used to resolve the [`toStringTag`](http://ecma-international.org/ecma-262/6.0/#sec-object.prototype.tostring) + * of values. + */ + var objectToString = objectProto.toString; + + /** Used to restore the original `_` reference in `_.noConflict`. */ + var oldDash = root._; + + /** Used to detect if a method is native. */ + var reIsNative = RegExp('^' + + funcToString.call(hasOwnProperty).replace(reRegExpChar, '\\$&') + .replace(/hasOwnProperty|(function).*?(?=\\\()| for .+?(?=\\\])/g, '$1.*?') + '$' + ); + + /** Built-in value references. */ + var Buffer = moduleExports ? context.Buffer : undefined, + Reflect = context.Reflect, + Symbol = context.Symbol, + Uint8Array = context.Uint8Array, + clearTimeout = context.clearTimeout, + enumerate = Reflect ? Reflect.enumerate : undefined, + getPrototypeOf = Object.getPrototypeOf, + getOwnPropertySymbols = Object.getOwnPropertySymbols, + iteratorSymbol = typeof (iteratorSymbol = Symbol && Symbol.iterator) == 'symbol' ? iteratorSymbol : undefined, + objectCreate = Object.create, + propertyIsEnumerable = objectProto.propertyIsEnumerable, + setTimeout = context.setTimeout, + splice = arrayProto.splice; + + /* Built-in method references for those with the same name as other `lodash` methods. */ + var nativeCeil = Math.ceil, + nativeFloor = Math.floor, + nativeIsFinite = context.isFinite, + nativeJoin = arrayProto.join, + nativeKeys = Object.keys, + nativeMax = Math.max, + nativeMin = Math.min, + nativeParseInt = context.parseInt, + nativeRandom = Math.random, + nativeReverse = arrayProto.reverse; + + /* Built-in method references that are verified to be native. */ + var Map = getNative(context, 'Map'), + Set = getNative(context, 'Set'), + WeakMap = getNative(context, 'WeakMap'), + nativeCreate = getNative(Object, 'create'); + + /** Used to store function metadata. */ + var metaMap = WeakMap && new WeakMap; + + /** Used to detect maps, sets, and weakmaps. */ + var mapCtorString = Map ? funcToString.call(Map) : '', + setCtorString = Set ? funcToString.call(Set) : '', + weakMapCtorString = WeakMap ? funcToString.call(WeakMap) : ''; + + /** Used to convert symbols to primitives and strings. */ + var symbolProto = Symbol ? Symbol.prototype : undefined, + symbolValueOf = Symbol ? symbolProto.valueOf : undefined, + symbolToString = Symbol ? symbolProto.toString : undefined; + + /** Used to lookup unminified function names. */ + var realNames = {}; + + /*------------------------------------------------------------------------*/ + + /** + * Creates a `lodash` object which wraps `value` to enable implicit method + * chaining. Methods that operate on and return arrays, collections, and + * functions can be chained together. Methods that retrieve a single value or + * may return a primitive value will automatically end the chain sequence and + * return the unwrapped value. Otherwise, the value must be unwrapped with + * `_#value`. + * + * Explicit chaining, which must be unwrapped with `_#value` in all cases, + * may be enabled using `_.chain`. + * + * The execution of chained methods is lazy, that is, it's deferred until + * `_#value` is implicitly or explicitly called. + * + * Lazy evaluation allows several methods to support shortcut fusion. Shortcut + * fusion is an optimization to merge iteratee calls; this avoids the creation + * of intermediate arrays and can greatly reduce the number of iteratee executions. + * Sections of a chain sequence qualify for shortcut fusion if the section is + * applied to an array of at least two hundred elements and any iteratees + * accept only one argument. The heuristic for whether a section qualifies + * for shortcut fusion is subject to change. + * + * Chaining is supported in custom builds as long as the `_#value` method is + * directly or indirectly included in the build. + * + * In addition to lodash methods, wrappers have `Array` and `String` methods. + * + * The wrapper `Array` methods are: + * `concat`, `join`, `pop`, `push`, `shift`, `sort`, `splice`, and `unshift` + * + * The wrapper `String` methods are: + * `replace` and `split` + * + * The wrapper methods that support shortcut fusion are: + * `at`, `compact`, `drop`, `dropRight`, `dropWhile`, `filter`, `find`, + * `findLast`, `head`, `initial`, `last`, `map`, `reject`, `reverse`, `slice`, + * `tail`, `take`, `takeRight`, `takeRightWhile`, `takeWhile`, and `toArray` + * + * The chainable wrapper methods are: + * `after`, `ary`, `assign`, `assignIn`, `assignInWith`, `assignWith`, `at`, + * `before`, `bind`, `bindAll`, `bindKey`, `castArray`, `chain`, `chunk`, + * `commit`, `compact`, `concat`, `conforms`, `constant`, `countBy`, `create`, + * `curry`, `debounce`, `defaults`, `defaultsDeep`, `defer`, `delay`, `difference`, + * `differenceBy`, `differenceWith`, `drop`, `dropRight`, `dropRightWhile`, + * `dropWhile`, `fill`, `filter`, `flatten`, `flattenDeep`, `flattenDepth`, + * `flip`, `flow`, `flowRight`, `fromPairs`, `functions`, `functionsIn`, + * `groupBy`, `initial`, `intersection`, `intersectionBy`, `intersectionWith`, + * `invert`, `invertBy`, `invokeMap`, `iteratee`, `keyBy`, `keys`, `keysIn`, + * `map`, `mapKeys`, `mapValues`, `matches`, `matchesProperty`, `memoize`, + * `merge`, `mergeWith`, `method`, `methodOf`, `mixin`, `negate`, `nthArg`, + * `omit`, `omitBy`, `once`, `orderBy`, `over`, `overArgs`, `overEvery`, + * `overSome`, `partial`, `partialRight`, `partition`, `pick`, `pickBy`, `plant`, + * `property`, `propertyOf`, `pull`, `pullAll`, `pullAllBy`, `pullAt`, `push`, + * `range`, `rangeRight`, `rearg`, `reject`, `remove`, `rest`, `reverse`, + * `sampleSize`, `set`, `setWith`, `shuffle`, `slice`, `sort`, `sortBy`, + * `splice`, `spread`, `tail`, `take`, `takeRight`, `takeRightWhile`, + * `takeWhile`, `tap`, `throttle`, `thru`, `toArray`, `toPairs`, `toPairsIn`, + * `toPath`, `toPlainObject`, `transform`, `unary`, `union`, `unionBy`, + * `unionWith`, `uniq`, `uniqBy`, `uniqWith`, `unset`, `unshift`, `unzip`, + * `unzipWith`, `values`, `valuesIn`, `without`, `wrap`, `xor`, `xorBy`, + * `xorWith`, `zip`, `zipObject`, `zipObjectDeep`, and `zipWith` + * + * The wrapper methods that are **not** chainable by default are: + * `add`, `attempt`, `camelCase`, `capitalize`, `ceil`, `clamp`, `clone`, + * `cloneDeep`, `cloneDeepWith`, `cloneWith`, `deburr`, `endsWith`, `eq`, + * `escape`, `escapeRegExp`, `every`, `find`, `findIndex`, `findKey`, `findLast`, + * `findLastIndex`, `findLastKey`, `floor`, `forEach`, `forEachRight`, `forIn`, + * `forInRight`, `forOwn`, `forOwnRight`, `get`, `gt`, `gte`, `has`, `hasIn`, + * `head`, `identity`, `includes`, `indexOf`, `inRange`, `invoke`, `isArguments`, + * `isArray`, `isArrayBuffer`, `isArrayLike`, `isArrayLikeObject`, `isBoolean`, + * `isBuffer`, `isDate`, `isElement`, `isEmpty`, `isEqual`, `isEqualWith`, + * `isError`, `isFinite`, `isFunction`, `isInteger`, `isLength`, `isMap`, + * `isMatch`, `isMatchWith`, `isNaN`, `isNative`, `isNil`, `isNull`, `isNumber`, + * `isObject`, `isObjectLike`, `isPlainObject`, `isRegExp`, `isSafeInteger`, + * `isSet`, `isString`, `isUndefined`, `isTypedArray`, `isWeakMap`, `isWeakSet`, + * `join`, `kebabCase`, `last`, `lastIndexOf`, `lowerCase`, `lowerFirst`, + * `lt`, `lte`, `max`, `maxBy`, `mean`, `min`, `minBy`, `noConflict`, `noop`, + * `now`, `pad`, `padEnd`, `padStart`, `parseInt`, `pop`, `random`, `reduce`, + * `reduceRight`, `repeat`, `result`, `round`, `runInContext`, `sample`, + * `shift`, `size`, `snakeCase`, `some`, `sortedIndex`, `sortedIndexBy`, + * `sortedLastIndex`, `sortedLastIndexBy`, `startCase`, `startsWith`, `subtract`, + * `sum`, `sumBy`, `template`, `times`, `toLower`, `toInteger`, `toLength`, + * `toNumber`, `toSafeInteger`, `toString`, `toUpper`, `trim`, `trimEnd`, + * `trimStart`, `truncate`, `unescape`, `uniqueId`, `upperCase`, `upperFirst`, + * `value`, and `words` + * + * @name _ + * @constructor + * @category Seq + * @param {*} value The value to wrap in a `lodash` instance. + * @returns {Object} Returns the new `lodash` wrapper instance. + * @example + * + * function square(n) { + * return n * n; + * } + * + * var wrapped = _([1, 2, 3]); + * + * // Returns an unwrapped value. + * wrapped.reduce(_.add); + * // => 6 + * + * // Returns a wrapped value. + * var squares = wrapped.map(square); + * + * _.isArray(squares); + * // => false + * + * _.isArray(squares.value()); + * // => true + */ + function lodash(value) { + if (isObjectLike(value) && !isArray(value) && !(value instanceof LazyWrapper)) { + if (value instanceof LodashWrapper) { + return value; + } + if (hasOwnProperty.call(value, '__wrapped__')) { + return wrapperClone(value); + } + } + return new LodashWrapper(value); + } + + /** + * The function whose prototype all chaining wrappers inherit from. + * + * @private + */ + function baseLodash() { + // No operation performed. + } + + /** + * The base constructor for creating `lodash` wrapper objects. + * + * @private + * @param {*} value The value to wrap. + * @param {boolean} [chainAll] Enable chaining for all wrapper methods. + */ + function LodashWrapper(value, chainAll) { + this.__wrapped__ = value; + this.__actions__ = []; + this.__chain__ = !!chainAll; + this.__index__ = 0; + this.__values__ = undefined; + } + + /** + * By default, the template delimiters used by lodash are like those in + * embedded Ruby (ERB). Change the following template settings to use + * alternative delimiters. + * + * @static + * @memberOf _ + * @type {Object} + */ + lodash.templateSettings = { + + /** + * Used to detect `data` property values to be HTML-escaped. + * + * @memberOf _.templateSettings + * @type {RegExp} + */ + 'escape': reEscape, + + /** + * Used to detect code to be evaluated. + * + * @memberOf _.templateSettings + * @type {RegExp} + */ + 'evaluate': reEvaluate, + + /** + * Used to detect `data` property values to inject. + * + * @memberOf _.templateSettings + * @type {RegExp} + */ + 'interpolate': reInterpolate, + + /** + * Used to reference the data object in the template text. + * + * @memberOf _.templateSettings + * @type {string} + */ + 'variable': '', + + /** + * Used to import variables into the compiled template. + * + * @memberOf _.templateSettings + * @type {Object} + */ + 'imports': { + + /** + * A reference to the `lodash` function. + * + * @memberOf _.templateSettings.imports + * @type {Function} + */ + '_': lodash + } + }; + + /*------------------------------------------------------------------------*/ + + /** + * Creates a lazy wrapper object which wraps `value` to enable lazy evaluation. + * + * @private + * @constructor + * @param {*} value The value to wrap. + */ + function LazyWrapper(value) { + this.__wrapped__ = value; + this.__actions__ = []; + this.__dir__ = 1; + this.__filtered__ = false; + this.__iteratees__ = []; + this.__takeCount__ = MAX_ARRAY_LENGTH; + this.__views__ = []; + } + + /** + * Creates a clone of the lazy wrapper object. + * + * @private + * @name clone + * @memberOf LazyWrapper + * @returns {Object} Returns the cloned `LazyWrapper` object. + */ + function lazyClone() { + var result = new LazyWrapper(this.__wrapped__); + result.__actions__ = copyArray(this.__actions__); + result.__dir__ = this.__dir__; + result.__filtered__ = this.__filtered__; + result.__iteratees__ = copyArray(this.__iteratees__); + result.__takeCount__ = this.__takeCount__; + result.__views__ = copyArray(this.__views__); + return result; + } + + /** + * Reverses the direction of lazy iteration. + * + * @private + * @name reverse + * @memberOf LazyWrapper + * @returns {Object} Returns the new reversed `LazyWrapper` object. + */ + function lazyReverse() { + if (this.__filtered__) { + var result = new LazyWrapper(this); + result.__dir__ = -1; + result.__filtered__ = true; + } else { + result = this.clone(); + result.__dir__ *= -1; + } + return result; + } + + /** + * Extracts the unwrapped value from its lazy wrapper. + * + * @private + * @name value + * @memberOf LazyWrapper + * @returns {*} Returns the unwrapped value. + */ + function lazyValue() { + var array = this.__wrapped__.value(), + dir = this.__dir__, + isArr = isArray(array), + isRight = dir < 0, + arrLength = isArr ? array.length : 0, + view = getView(0, arrLength, this.__views__), + start = view.start, + end = view.end, + length = end - start, + index = isRight ? end : (start - 1), + iteratees = this.__iteratees__, + iterLength = iteratees.length, + resIndex = 0, + takeCount = nativeMin(length, this.__takeCount__); + + if (!isArr || arrLength < LARGE_ARRAY_SIZE || + (arrLength == length && takeCount == length)) { + return baseWrapperValue(array, this.__actions__); + } + var result = []; + + outer: + while (length-- && resIndex < takeCount) { + index += dir; + + var iterIndex = -1, + value = array[index]; + + while (++iterIndex < iterLength) { + var data = iteratees[iterIndex], + iteratee = data.iteratee, + type = data.type, + computed = iteratee(value); + + if (type == LAZY_MAP_FLAG) { + value = computed; + } else if (!computed) { + if (type == LAZY_FILTER_FLAG) { + continue outer; + } else { + break outer; + } + } + } + result[resIndex++] = value; + } + return result; + } + + /*------------------------------------------------------------------------*/ + + /** + * Creates an hash object. + * + * @private + * @constructor + * @returns {Object} Returns the new hash object. + */ + function Hash() {} + + /** + * Removes `key` and its value from the hash. + * + * @private + * @param {Object} hash The hash to modify. + * @param {string} key The key of the value to remove. + * @returns {boolean} Returns `true` if the entry was removed, else `false`. + */ + function hashDelete(hash, key) { + return hashHas(hash, key) && delete hash[key]; + } + + /** + * Gets the hash value for `key`. + * + * @private + * @param {Object} hash The hash to query. + * @param {string} key The key of the value to get. + * @returns {*} Returns the entry value. + */ + function hashGet(hash, key) { + if (nativeCreate) { + var result = hash[key]; + return result === HASH_UNDEFINED ? undefined : result; + } + return hasOwnProperty.call(hash, key) ? hash[key] : undefined; + } + + /** + * Checks if a hash value for `key` exists. + * + * @private + * @param {Object} hash The hash to query. + * @param {string} key The key of the entry to check. + * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`. + */ + function hashHas(hash, key) { + return nativeCreate ? hash[key] !== undefined : hasOwnProperty.call(hash, key); + } + + /** + * Sets the hash `key` to `value`. + * + * @private + * @param {Object} hash The hash to modify. + * @param {string} key The key of the value to set. + * @param {*} value The value to set. + */ + function hashSet(hash, key, value) { + hash[key] = (nativeCreate && value === undefined) ? HASH_UNDEFINED : value; + } + + /*------------------------------------------------------------------------*/ + + /** + * Creates a map cache object to store key-value pairs. + * + * @private + * @constructor + * @param {Array} [values] The values to cache. + */ + function MapCache(values) { + var index = -1, + length = values ? values.length : 0; + + this.clear(); + while (++index < length) { + var entry = values[index]; + this.set(entry[0], entry[1]); + } + } + + /** + * Removes all key-value entries from the map. + * + * @private + * @name clear + * @memberOf MapCache + */ + function mapClear() { + this.__data__ = { + 'hash': new Hash, + 'map': Map ? new Map : [], + 'string': new Hash + }; + } + + /** + * Removes `key` and its value from the map. + * + * @private + * @name delete + * @memberOf MapCache + * @param {string} key The key of the value to remove. + * @returns {boolean} Returns `true` if the entry was removed, else `false`. + */ + function mapDelete(key) { + var data = this.__data__; + if (isKeyable(key)) { + return hashDelete(typeof key == 'string' ? data.string : data.hash, key); + } + return Map ? data.map['delete'](key) : assocDelete(data.map, key); + } + + /** + * Gets the map value for `key`. + * + * @private + * @name get + * @memberOf MapCache + * @param {string} key The key of the value to get. + * @returns {*} Returns the entry value. + */ + function mapGet(key) { + var data = this.__data__; + if (isKeyable(key)) { + return hashGet(typeof key == 'string' ? data.string : data.hash, key); + } + return Map ? data.map.get(key) : assocGet(data.map, key); + } + + /** + * Checks if a map value for `key` exists. + * + * @private + * @name has + * @memberOf MapCache + * @param {string} key The key of the entry to check. + * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`. + */ + function mapHas(key) { + var data = this.__data__; + if (isKeyable(key)) { + return hashHas(typeof key == 'string' ? data.string : data.hash, key); + } + return Map ? data.map.has(key) : assocHas(data.map, key); + } + + /** + * Sets the map `key` to `value`. + * + * @private + * @name set + * @memberOf MapCache + * @param {string} key The key of the value to set. + * @param {*} value The value to set. + * @returns {Object} Returns the map cache object. + */ + function mapSet(key, value) { + var data = this.__data__; + if (isKeyable(key)) { + hashSet(typeof key == 'string' ? data.string : data.hash, key, value); + } else if (Map) { + data.map.set(key, value); + } else { + assocSet(data.map, key, value); + } + return this; + } + + /*------------------------------------------------------------------------*/ + + /** + * + * Creates a set cache object to store unique values. + * + * @private + * @constructor + * @param {Array} [values] The values to cache. + */ + function SetCache(values) { + var index = -1, + length = values ? values.length : 0; + + this.__data__ = new MapCache; + while (++index < length) { + this.push(values[index]); + } + } + + /** + * Checks if `value` is in `cache`. + * + * @private + * @param {Object} cache The set cache to search. + * @param {*} value The value to search for. + * @returns {number} Returns `true` if `value` is found, else `false`. + */ + function cacheHas(cache, value) { + var map = cache.__data__; + if (isKeyable(value)) { + var data = map.__data__, + hash = typeof value == 'string' ? data.string : data.hash; + + return hash[value] === HASH_UNDEFINED; + } + return map.has(value); + } + + /** + * Adds `value` to the set cache. + * + * @private + * @name push + * @memberOf SetCache + * @param {*} value The value to cache. + */ + function cachePush(value) { + var map = this.__data__; + if (isKeyable(value)) { + var data = map.__data__, + hash = typeof value == 'string' ? data.string : data.hash; + + hash[value] = HASH_UNDEFINED; + } + else { + map.set(value, HASH_UNDEFINED); + } + } + + /*------------------------------------------------------------------------*/ + + /** + * Creates a stack cache object to store key-value pairs. + * + * @private + * @constructor + * @param {Array} [values] The values to cache. + */ + function Stack(values) { + var index = -1, + length = values ? values.length : 0; + + this.clear(); + while (++index < length) { + var entry = values[index]; + this.set(entry[0], entry[1]); + } + } + + /** + * Removes all key-value entries from the stack. + * + * @private + * @name clear + * @memberOf Stack + */ + function stackClear() { + this.__data__ = { 'array': [], 'map': null }; + } + + /** + * Removes `key` and its value from the stack. + * + * @private + * @name delete + * @memberOf Stack + * @param {string} key The key of the value to remove. + * @returns {boolean} Returns `true` if the entry was removed, else `false`. + */ + function stackDelete(key) { + var data = this.__data__, + array = data.array; + + return array ? assocDelete(array, key) : data.map['delete'](key); + } + + /** + * Gets the stack value for `key`. + * + * @private + * @name get + * @memberOf Stack + * @param {string} key The key of the value to get. + * @returns {*} Returns the entry value. + */ + function stackGet(key) { + var data = this.__data__, + array = data.array; + + return array ? assocGet(array, key) : data.map.get(key); + } + + /** + * Checks if a stack value for `key` exists. + * + * @private + * @name has + * @memberOf Stack + * @param {string} key The key of the entry to check. + * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`. + */ + function stackHas(key) { + var data = this.__data__, + array = data.array; + + return array ? assocHas(array, key) : data.map.has(key); + } + + /** + * Sets the stack `key` to `value`. + * + * @private + * @name set + * @memberOf Stack + * @param {string} key The key of the value to set. + * @param {*} value The value to set. + * @returns {Object} Returns the stack cache object. + */ + function stackSet(key, value) { + var data = this.__data__, + array = data.array; + + if (array) { + if (array.length < (LARGE_ARRAY_SIZE - 1)) { + assocSet(array, key, value); + } else { + data.array = null; + data.map = new MapCache(array); + } + } + var map = data.map; + if (map) { + map.set(key, value); + } + return this; + } + + /*------------------------------------------------------------------------*/ + + /** + * Removes `key` and its value from the associative array. + * + * @private + * @param {Array} array The array to query. + * @param {string} key The key of the value to remove. + * @returns {boolean} Returns `true` if the entry was removed, else `false`. + */ + function assocDelete(array, key) { + var index = assocIndexOf(array, key); + if (index < 0) { + return false; + } + var lastIndex = array.length - 1; + if (index == lastIndex) { + array.pop(); + } else { + splice.call(array, index, 1); + } + return true; + } + + /** + * Gets the associative array value for `key`. + * + * @private + * @param {Array} array The array to query. + * @param {string} key The key of the value to get. + * @returns {*} Returns the entry value. + */ + function assocGet(array, key) { + var index = assocIndexOf(array, key); + return index < 0 ? undefined : array[index][1]; + } + + /** + * Checks if an associative array value for `key` exists. + * + * @private + * @param {Array} array The array to query. + * @param {string} key The key of the entry to check. + * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`. + */ + function assocHas(array, key) { + return assocIndexOf(array, key) > -1; + } + + /** + * Gets the index at which the first occurrence of `key` is found in `array` + * of key-value pairs. + * + * @private + * @param {Array} array The array to search. + * @param {*} key The key to search for. + * @returns {number} Returns the index of the matched value, else `-1`. + */ + function assocIndexOf(array, key) { + var length = array.length; + while (length--) { + if (eq(array[length][0], key)) { + return length; + } + } + return -1; + } + + /** + * Sets the associative array `key` to `value`. + * + * @private + * @param {Array} array The array to modify. + * @param {string} key The key of the value to set. + * @param {*} value The value to set. + */ + function assocSet(array, key, value) { + var index = assocIndexOf(array, key); + if (index < 0) { + array.push([key, value]); + } else { + array[index][1] = value; + } + } + + /*------------------------------------------------------------------------*/ + + /** + * Used by `_.defaults` to customize its `_.assignIn` use. + * + * @private + * @param {*} objValue The destination value. + * @param {*} srcValue The source value. + * @param {string} key The key of the property to assign. + * @param {Object} object The parent object of `objValue`. + * @returns {*} Returns the value to assign. + */ + function assignInDefaults(objValue, srcValue, key, object) { + if (objValue === undefined || + (eq(objValue, objectProto[key]) && !hasOwnProperty.call(object, key))) { + return srcValue; + } + return objValue; + } + + /** + * This function is like `assignValue` except that it doesn't assign `undefined` values. + * + * @private + * @param {Object} object The object to modify. + * @param {string} key The key of the property to assign. + * @param {*} value The value to assign. + */ + function assignMergeValue(object, key, value) { + if ((value !== undefined && !eq(object[key], value)) || + (typeof key == 'number' && value === undefined && !(key in object))) { + object[key] = value; + } + } + + /** + * Assigns `value` to `key` of `object` if the existing value is not equivalent + * using [`SameValueZero`](http://ecma-international.org/ecma-262/6.0/#sec-samevaluezero) + * for equality comparisons. + * + * @private + * @param {Object} object The object to modify. + * @param {string} key The key of the property to assign. + * @param {*} value The value to assign. + */ + function assignValue(object, key, value) { + var objValue = object[key]; + if (!(hasOwnProperty.call(object, key) && eq(objValue, value)) || + (value === undefined && !(key in object))) { + object[key] = value; + } + } + + /** + * Aggregates elements of `collection` on `accumulator` with keys transformed + * by `iteratee` and values set by `setter`. + * + * @private + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} setter The function to set `accumulator` values. + * @param {Function} iteratee The iteratee to transform keys. + * @param {Object} accumulator The initial aggregated object. + * @returns {Function} Returns `accumulator`. + */ + function baseAggregator(collection, setter, iteratee, accumulator) { + baseEach(collection, function(value, key, collection) { + setter(accumulator, value, iteratee(value), collection); + }); + return accumulator; + } + + /** + * The base implementation of `_.assign` without support for multiple sources + * or `customizer` functions. + * + * @private + * @param {Object} object The destination object. + * @param {Object} source The source object. + * @returns {Object} Returns `object`. + */ + function baseAssign(object, source) { + return object && copyObject(source, keys(source), object); + } + + /** + * The base implementation of `_.at` without support for individual paths. + * + * @private + * @param {Object} object The object to iterate over. + * @param {string[]} paths The property paths of elements to pick. + * @returns {Array} Returns the new array of picked elements. + */ + function baseAt(object, paths) { + var index = -1, + isNil = object == null, + length = paths.length, + result = Array(length); + + while (++index < length) { + result[index] = isNil ? undefined : get(object, paths[index]); + } + return result; + } + + /** + * Casts `value` to an empty array if it's not an array like object. + * + * @private + * @param {*} value The value to inspect. + * @returns {Array} Returns the array-like object. + */ + function baseCastArrayLikeObject(value) { + return isArrayLikeObject(value) ? value : []; + } + + /** + * Casts `value` to `identity` if it's not a function. + * + * @private + * @param {*} value The value to inspect. + * @returns {Array} Returns the array-like object. + */ + function baseCastFunction(value) { + return typeof value == 'function' ? value : identity; + } + + /** + * Casts `value` to a path array if it's not one. + * + * @private + * @param {*} value The value to inspect. + * @returns {Array} Returns the cast property path array. + */ + function baseCastPath(value) { + return isArray(value) ? value : stringToPath(value); + } + + /** + * The base implementation of `_.clamp` which doesn't coerce arguments to numbers. + * + * @private + * @param {number} number The number to clamp. + * @param {number} [lower] The lower bound. + * @param {number} upper The upper bound. + * @returns {number} Returns the clamped number. + */ + function baseClamp(number, lower, upper) { + if (number === number) { + if (upper !== undefined) { + number = number <= upper ? number : upper; + } + if (lower !== undefined) { + number = number >= lower ? number : lower; + } + } + return number; + } + + /** + * The base implementation of `_.clone` and `_.cloneDeep` which tracks + * traversed objects. + * + * @private + * @param {*} value The value to clone. + * @param {boolean} [isDeep] Specify a deep clone. + * @param {Function} [customizer] The function to customize cloning. + * @param {string} [key] The key of `value`. + * @param {Object} [object] The parent object of `value`. + * @param {Object} [stack] Tracks traversed objects and their clone counterparts. + * @returns {*} Returns the cloned value. + */ + function baseClone(value, isDeep, customizer, key, object, stack) { + var result; + if (customizer) { + result = object ? customizer(value, key, object, stack) : customizer(value); + } + if (result !== undefined) { + return result; + } + if (!isObject(value)) { + return value; + } + var isArr = isArray(value); + if (isArr) { + result = initCloneArray(value); + if (!isDeep) { + return copyArray(value, result); + } + } else { + var tag = getTag(value), + isFunc = tag == funcTag || tag == genTag; + + if (isBuffer(value)) { + return cloneBuffer(value, isDeep); + } + if (tag == objectTag || tag == argsTag || (isFunc && !object)) { + if (isHostObject(value)) { + return object ? value : {}; + } + result = initCloneObject(isFunc ? {} : value); + if (!isDeep) { + return copySymbols(value, baseAssign(result, value)); + } + } else { + if (!cloneableTags[tag]) { + return object ? value : {}; + } + result = initCloneByTag(value, tag, isDeep); + } + } + // Check for circular references and return its corresponding clone. + stack || (stack = new Stack); + var stacked = stack.get(value); + if (stacked) { + return stacked; + } + stack.set(value, result); + + // Recursively populate clone (susceptible to call stack limits). + (isArr ? arrayEach : baseForOwn)(value, function(subValue, key) { + assignValue(result, key, baseClone(subValue, isDeep, customizer, key, value, stack)); + }); + return isArr ? result : copySymbols(value, result); + } + + /** + * The base implementation of `_.conforms` which doesn't clone `source`. + * + * @private + * @param {Object} source The object of property predicates to conform to. + * @returns {Function} Returns the new function. + */ + function baseConforms(source) { + var props = keys(source), + length = props.length; + + return function(object) { + if (object == null) { + return !length; + } + var index = length; + while (index--) { + var key = props[index], + predicate = source[key], + value = object[key]; + + if ((value === undefined && !(key in Object(object))) || !predicate(value)) { + return false; + } + } + return true; + }; + } + + /** + * The base implementation of `_.create` without support for assigning + * properties to the created object. + * + * @private + * @param {Object} prototype The object to inherit from. + * @returns {Object} Returns the new object. + */ + function baseCreate(proto) { + return isObject(proto) ? objectCreate(proto) : {}; + } + + /** + * The base implementation of `_.delay` and `_.defer` which accepts an array + * of `func` arguments. + * + * @private + * @param {Function} func The function to delay. + * @param {number} wait The number of milliseconds to delay invocation. + * @param {Object} args The arguments to provide to `func`. + * @returns {number} Returns the timer id. + */ + function baseDelay(func, wait, args) { + if (typeof func != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + return setTimeout(function() { func.apply(undefined, args); }, wait); + } + + /** + * The base implementation of methods like `_.difference` without support for + * excluding multiple arrays or iteratee shorthands. + * + * @private + * @param {Array} array The array to inspect. + * @param {Array} values The values to exclude. + * @param {Function} [iteratee] The iteratee invoked per element. + * @param {Function} [comparator] The comparator invoked per element. + * @returns {Array} Returns the new array of filtered values. + */ + function baseDifference(array, values, iteratee, comparator) { + var index = -1, + includes = arrayIncludes, + isCommon = true, + length = array.length, + result = [], + valuesLength = values.length; + + if (!length) { + return result; + } + if (iteratee) { + values = arrayMap(values, baseUnary(iteratee)); + } + if (comparator) { + includes = arrayIncludesWith; + isCommon = false; + } + else if (values.length >= LARGE_ARRAY_SIZE) { + includes = cacheHas; + isCommon = false; + values = new SetCache(values); + } + outer: + while (++index < length) { + var value = array[index], + computed = iteratee ? iteratee(value) : value; + + if (isCommon && computed === computed) { + var valuesIndex = valuesLength; + while (valuesIndex--) { + if (values[valuesIndex] === computed) { + continue outer; + } + } + result.push(value); + } + else if (!includes(values, computed, comparator)) { + result.push(value); + } + } + return result; + } + + /** + * The base implementation of `_.forEach` without support for iteratee shorthands. + * + * @private + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @returns {Array|Object} Returns `collection`. + */ + var baseEach = createBaseEach(baseForOwn); + + /** + * The base implementation of `_.forEachRight` without support for iteratee shorthands. + * + * @private + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @returns {Array|Object} Returns `collection`. + */ + var baseEachRight = createBaseEach(baseForOwnRight, true); + + /** + * The base implementation of `_.every` without support for iteratee shorthands. + * + * @private + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} predicate The function invoked per iteration. + * @returns {boolean} Returns `true` if all elements pass the predicate check, else `false` + */ + function baseEvery(collection, predicate) { + var result = true; + baseEach(collection, function(value, index, collection) { + result = !!predicate(value, index, collection); + return result; + }); + return result; + } + + /** + * The base implementation of `_.fill` without an iteratee call guard. + * + * @private + * @param {Array} array The array to fill. + * @param {*} value The value to fill `array` with. + * @param {number} [start=0] The start position. + * @param {number} [end=array.length] The end position. + * @returns {Array} Returns `array`. + */ + function baseFill(array, value, start, end) { + var length = array.length; + + start = toInteger(start); + if (start < 0) { + start = -start > length ? 0 : (length + start); + } + end = (end === undefined || end > length) ? length : toInteger(end); + if (end < 0) { + end += length; + } + end = start > end ? 0 : toLength(end); + while (start < end) { + array[start++] = value; + } + return array; + } + + /** + * The base implementation of `_.filter` without support for iteratee shorthands. + * + * @private + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} predicate The function invoked per iteration. + * @returns {Array} Returns the new filtered array. + */ + function baseFilter(collection, predicate) { + var result = []; + baseEach(collection, function(value, index, collection) { + if (predicate(value, index, collection)) { + result.push(value); + } + }); + return result; + } + + /** + * The base implementation of `_.flatten` with support for restricting flattening. + * + * @private + * @param {Array} array The array to flatten. + * @param {number} depth The maximum recursion depth. + * @param {boolean} [isStrict] Restrict flattening to arrays-like objects. + * @param {Array} [result=[]] The initial result value. + * @returns {Array} Returns the new flattened array. + */ + function baseFlatten(array, depth, isStrict, result) { + result || (result = []); + + var index = -1, + length = array.length; + + while (++index < length) { + var value = array[index]; + if (depth > 0 && isArrayLikeObject(value) && + (isStrict || isArray(value) || isArguments(value))) { + if (depth > 1) { + // Recursively flatten arrays (susceptible to call stack limits). + baseFlatten(value, depth - 1, isStrict, result); + } else { + arrayPush(result, value); + } + } else if (!isStrict) { + result[result.length] = value; + } + } + return result; + } + + /** + * The base implementation of `baseForIn` and `baseForOwn` which iterates + * over `object` properties returned by `keysFunc` invoking `iteratee` for + * each property. Iteratee functions may exit iteration early by explicitly + * returning `false`. + * + * @private + * @param {Object} object The object to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @param {Function} keysFunc The function to get the keys of `object`. + * @returns {Object} Returns `object`. + */ + var baseFor = createBaseFor(); + + /** + * This function is like `baseFor` except that it iterates over properties + * in the opposite order. + * + * @private + * @param {Object} object The object to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @param {Function} keysFunc The function to get the keys of `object`. + * @returns {Object} Returns `object`. + */ + var baseForRight = createBaseFor(true); + + /** + * The base implementation of `_.forIn` without support for iteratee shorthands. + * + * @private + * @param {Object} object The object to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @returns {Object} Returns `object`. + */ + function baseForIn(object, iteratee) { + return object == null ? object : baseFor(object, iteratee, keysIn); + } + + /** + * The base implementation of `_.forOwn` without support for iteratee shorthands. + * + * @private + * @param {Object} object The object to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @returns {Object} Returns `object`. + */ + function baseForOwn(object, iteratee) { + return object && baseFor(object, iteratee, keys); + } + + /** + * The base implementation of `_.forOwnRight` without support for iteratee shorthands. + * + * @private + * @param {Object} object The object to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @returns {Object} Returns `object`. + */ + function baseForOwnRight(object, iteratee) { + return object && baseForRight(object, iteratee, keys); + } + + /** + * The base implementation of `_.functions` which creates an array of + * `object` function property names filtered from `props`. + * + * @private + * @param {Object} object The object to inspect. + * @param {Array} props The property names to filter. + * @returns {Array} Returns the new array of filtered property names. + */ + function baseFunctions(object, props) { + return arrayFilter(props, function(key) { + return isFunction(object[key]); + }); + } + + /** + * The base implementation of `_.get` without support for default values. + * + * @private + * @param {Object} object The object to query. + * @param {Array|string} path The path of the property to get. + * @returns {*} Returns the resolved value. + */ + function baseGet(object, path) { + path = isKey(path, object) ? [path + ''] : baseCastPath(path); + + var index = 0, + length = path.length; + + while (object != null && index < length) { + object = object[path[index++]]; + } + return (index && index == length) ? object : undefined; + } + + /** + * The base implementation of `_.has` without support for deep paths. + * + * @private + * @param {Object} object The object to query. + * @param {Array|string} key The key to check. + * @returns {boolean} Returns `true` if `key` exists, else `false`. + */ + function baseHas(object, key) { + // Avoid a bug in IE 10-11 where objects with a [[Prototype]] of `null`, + // that are composed entirely of index properties, return `false` for + // `hasOwnProperty` checks of them. + return hasOwnProperty.call(object, key) || + (typeof object == 'object' && key in object && getPrototypeOf(object) === null); + } + + /** + * The base implementation of `_.hasIn` without support for deep paths. + * + * @private + * @param {Object} object The object to query. + * @param {Array|string} key The key to check. + * @returns {boolean} Returns `true` if `key` exists, else `false`. + */ + function baseHasIn(object, key) { + return key in Object(object); + } + + /** + * The base implementation of `_.inRange` which doesn't coerce arguments to numbers. + * + * @private + * @param {number} number The number to check. + * @param {number} start The start of the range. + * @param {number} end The end of the range. + * @returns {boolean} Returns `true` if `number` is in the range, else `false`. + */ + function baseInRange(number, start, end) { + return number >= nativeMin(start, end) && number < nativeMax(start, end); + } + + /** + * The base implementation of methods like `_.intersection`, without support + * for iteratee shorthands, that accepts an array of arrays to inspect. + * + * @private + * @param {Array} arrays The arrays to inspect. + * @param {Function} [iteratee] The iteratee invoked per element. + * @param {Function} [comparator] The comparator invoked per element. + * @returns {Array} Returns the new array of shared values. + */ + function baseIntersection(arrays, iteratee, comparator) { + var includes = comparator ? arrayIncludesWith : arrayIncludes, + othLength = arrays.length, + othIndex = othLength, + caches = Array(othLength), + result = []; + + while (othIndex--) { + var array = arrays[othIndex]; + if (othIndex && iteratee) { + array = arrayMap(array, baseUnary(iteratee)); + } + caches[othIndex] = !comparator && (iteratee || array.length >= 120) + ? new SetCache(othIndex && array) + : undefined; + } + array = arrays[0]; + + var index = -1, + length = array.length, + seen = caches[0]; + + outer: + while (++index < length) { + var value = array[index], + computed = iteratee ? iteratee(value) : value; + + if (!(seen + ? cacheHas(seen, computed) + : includes(result, computed, comparator) + )) { + var othIndex = othLength; + while (--othIndex) { + var cache = caches[othIndex]; + if (!(cache + ? cacheHas(cache, computed) + : includes(arrays[othIndex], computed, comparator)) + ) { + continue outer; + } + } + if (seen) { + seen.push(computed); + } + result.push(value); + } + } + return result; + } + + /** + * The base implementation of `_.invert` and `_.invertBy` which inverts + * `object` with values transformed by `iteratee` and set by `setter`. + * + * @private + * @param {Object} object The object to iterate over. + * @param {Function} setter The function to set `accumulator` values. + * @param {Function} iteratee The iteratee to transform values. + * @param {Object} accumulator The initial inverted object. + * @returns {Function} Returns `accumulator`. + */ + function baseInverter(object, setter, iteratee, accumulator) { + baseForOwn(object, function(value, key, object) { + setter(accumulator, iteratee(value), key, object); + }); + return accumulator; + } + + /** + * The base implementation of `_.invoke` without support for individual + * method arguments. + * + * @private + * @param {Object} object The object to query. + * @param {Array|string} path The path of the method to invoke. + * @param {Array} args The arguments to invoke the method with. + * @returns {*} Returns the result of the invoked method. + */ + function baseInvoke(object, path, args) { + if (!isKey(path, object)) { + path = baseCastPath(path); + object = parent(object, path); + path = last(path); + } + var func = object == null ? object : object[path]; + return func == null ? undefined : apply(func, object, args); + } + + /** + * The base implementation of `_.isEqual` which supports partial comparisons + * and tracks traversed objects. + * + * @private + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @param {Function} [customizer] The function to customize comparisons. + * @param {boolean} [bitmask] The bitmask of comparison flags. + * The bitmask may be composed of the following flags: + * 1 - Unordered comparison + * 2 - Partial comparison + * @param {Object} [stack] Tracks traversed `value` and `other` objects. + * @returns {boolean} Returns `true` if the values are equivalent, else `false`. + */ + function baseIsEqual(value, other, customizer, bitmask, stack) { + if (value === other) { + return true; + } + if (value == null || other == null || (!isObject(value) && !isObjectLike(other))) { + return value !== value && other !== other; + } + return baseIsEqualDeep(value, other, baseIsEqual, customizer, bitmask, stack); + } + + /** + * A specialized version of `baseIsEqual` for arrays and objects which performs + * deep comparisons and tracks traversed objects enabling objects with circular + * references to be compared. + * + * @private + * @param {Object} object The object to compare. + * @param {Object} other The other object to compare. + * @param {Function} equalFunc The function to determine equivalents of values. + * @param {Function} [customizer] The function to customize comparisons. + * @param {number} [bitmask] The bitmask of comparison flags. See `baseIsEqual` for more details. + * @param {Object} [stack] Tracks traversed `object` and `other` objects. + * @returns {boolean} Returns `true` if the objects are equivalent, else `false`. + */ + function baseIsEqualDeep(object, other, equalFunc, customizer, bitmask, stack) { + var objIsArr = isArray(object), + othIsArr = isArray(other), + objTag = arrayTag, + othTag = arrayTag; + + if (!objIsArr) { + objTag = getTag(object); + if (objTag == argsTag) { + objTag = objectTag; + } else if (objTag != objectTag) { + objIsArr = isTypedArray(object); + } + } + if (!othIsArr) { + othTag = getTag(other); + if (othTag == argsTag) { + othTag = objectTag; + } else if (othTag != objectTag) { + othIsArr = isTypedArray(other); + } + } + var objIsObj = objTag == objectTag && !isHostObject(object), + othIsObj = othTag == objectTag && !isHostObject(other), + isSameTag = objTag == othTag; + + if (isSameTag && !(objIsArr || objIsObj)) { + return equalByTag(object, other, objTag, equalFunc, customizer, bitmask); + } + var isPartial = bitmask & PARTIAL_COMPARE_FLAG; + if (!isPartial) { + var objIsWrapped = objIsObj && hasOwnProperty.call(object, '__wrapped__'), + othIsWrapped = othIsObj && hasOwnProperty.call(other, '__wrapped__'); + + if (objIsWrapped || othIsWrapped) { + return equalFunc(objIsWrapped ? object.value() : object, othIsWrapped ? other.value() : other, customizer, bitmask, stack); + } + } + if (!isSameTag) { + return false; + } + stack || (stack = new Stack); + return (objIsArr ? equalArrays : equalObjects)(object, other, equalFunc, customizer, bitmask, stack); + } + + /** + * The base implementation of `_.isMatch` without support for iteratee shorthands. + * + * @private + * @param {Object} object The object to inspect. + * @param {Object} source The object of property values to match. + * @param {Array} matchData The property names, values, and compare flags to match. + * @param {Function} [customizer] The function to customize comparisons. + * @returns {boolean} Returns `true` if `object` is a match, else `false`. + */ + function baseIsMatch(object, source, matchData, customizer) { + var index = matchData.length, + length = index, + noCustomizer = !customizer; + + if (object == null) { + return !length; + } + object = Object(object); + while (index--) { + var data = matchData[index]; + if ((noCustomizer && data[2]) + ? data[1] !== object[data[0]] + : !(data[0] in object) + ) { + return false; + } + } + while (++index < length) { + data = matchData[index]; + var key = data[0], + objValue = object[key], + srcValue = data[1]; + + if (noCustomizer && data[2]) { + if (objValue === undefined && !(key in object)) { + return false; + } + } else { + var stack = new Stack, + result = customizer ? customizer(objValue, srcValue, key, object, source, stack) : undefined; + + if (!(result === undefined + ? baseIsEqual(srcValue, objValue, customizer, UNORDERED_COMPARE_FLAG | PARTIAL_COMPARE_FLAG, stack) + : result + )) { + return false; + } + } + } + return true; + } + + /** + * The base implementation of `_.iteratee`. + * + * @private + * @param {*} [value=_.identity] The value to convert to an iteratee. + * @returns {Function} Returns the iteratee. + */ + function baseIteratee(value) { + var type = typeof value; + if (type == 'function') { + return value; + } + if (value == null) { + return identity; + } + if (type == 'object') { + return isArray(value) + ? baseMatchesProperty(value[0], value[1]) + : baseMatches(value); + } + return property(value); + } + + /** + * The base implementation of `_.keys` which doesn't skip the constructor + * property of prototypes or treat sparse arrays as dense. + * + * @private + * @param {Object} object The object to query. + * @returns {Array} Returns the array of property names. + */ + function baseKeys(object) { + return nativeKeys(Object(object)); + } + + /** + * The base implementation of `_.keysIn` which doesn't skip the constructor + * property of prototypes or treat sparse arrays as dense. + * + * @private + * @param {Object} object The object to query. + * @returns {Array} Returns the array of property names. + */ + function baseKeysIn(object) { + object = object == null ? object : Object(object); + + var result = []; + for (var key in object) { + result.push(key); + } + return result; + } + + // Fallback for IE < 9 with es6-shim. + if (enumerate && !propertyIsEnumerable.call({ 'valueOf': 1 }, 'valueOf')) { + baseKeysIn = function(object) { + return iteratorToArray(enumerate(object)); + }; + } + + /** + * The base implementation of `_.map` without support for iteratee shorthands. + * + * @private + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @returns {Array} Returns the new mapped array. + */ + function baseMap(collection, iteratee) { + var index = -1, + result = isArrayLike(collection) ? Array(collection.length) : []; + + baseEach(collection, function(value, key, collection) { + result[++index] = iteratee(value, key, collection); + }); + return result; + } + + /** + * The base implementation of `_.matches` which doesn't clone `source`. + * + * @private + * @param {Object} source The object of property values to match. + * @returns {Function} Returns the new function. + */ + function baseMatches(source) { + var matchData = getMatchData(source); + if (matchData.length == 1 && matchData[0][2]) { + var key = matchData[0][0], + value = matchData[0][1]; + + return function(object) { + if (object == null) { + return false; + } + return object[key] === value && + (value !== undefined || (key in Object(object))); + }; + } + return function(object) { + return object === source || baseIsMatch(object, source, matchData); + }; + } + + /** + * The base implementation of `_.matchesProperty` which doesn't clone `srcValue`. + * + * @private + * @param {string} path The path of the property to get. + * @param {*} srcValue The value to match. + * @returns {Function} Returns the new function. + */ + function baseMatchesProperty(path, srcValue) { + return function(object) { + var objValue = get(object, path); + return (objValue === undefined && objValue === srcValue) + ? hasIn(object, path) + : baseIsEqual(srcValue, objValue, undefined, UNORDERED_COMPARE_FLAG | PARTIAL_COMPARE_FLAG); + }; + } + + /** + * The base implementation of `_.merge` without support for multiple sources. + * + * @private + * @param {Object} object The destination object. + * @param {Object} source The source object. + * @param {number} srcIndex The index of `source`. + * @param {Function} [customizer] The function to customize merged values. + * @param {Object} [stack] Tracks traversed source values and their merged counterparts. + */ + function baseMerge(object, source, srcIndex, customizer, stack) { + if (object === source) { + return; + } + var props = (isArray(source) || isTypedArray(source)) + ? undefined + : keysIn(source); + + arrayEach(props || source, function(srcValue, key) { + if (props) { + key = srcValue; + srcValue = source[key]; + } + if (isObject(srcValue)) { + stack || (stack = new Stack); + baseMergeDeep(object, source, key, srcIndex, baseMerge, customizer, stack); + } + else { + var newValue = customizer + ? customizer(object[key], srcValue, (key + ''), object, source, stack) + : undefined; + + if (newValue === undefined) { + newValue = srcValue; + } + assignMergeValue(object, key, newValue); + } + }); + } + + /** + * A specialized version of `baseMerge` for arrays and objects which performs + * deep merges and tracks traversed objects enabling objects with circular + * references to be merged. + * + * @private + * @param {Object} object The destination object. + * @param {Object} source The source object. + * @param {string} key The key of the value to merge. + * @param {number} srcIndex The index of `source`. + * @param {Function} mergeFunc The function to merge values. + * @param {Function} [customizer] The function to customize assigned values. + * @param {Object} [stack] Tracks traversed source values and their merged counterparts. + */ + function baseMergeDeep(object, source, key, srcIndex, mergeFunc, customizer, stack) { + var objValue = object[key], + srcValue = source[key], + stacked = stack.get(srcValue); + + if (stacked) { + assignMergeValue(object, key, stacked); + return; + } + var newValue = customizer + ? customizer(objValue, srcValue, (key + ''), object, source, stack) + : undefined; + + var isCommon = newValue === undefined; + + if (isCommon) { + newValue = srcValue; + if (isArray(srcValue) || isTypedArray(srcValue)) { + if (isArray(objValue)) { + newValue = objValue; + } + else if (isArrayLikeObject(objValue)) { + newValue = copyArray(objValue); + } + else { + isCommon = false; + newValue = baseClone(srcValue, true); + } + } + else if (isPlainObject(srcValue) || isArguments(srcValue)) { + if (isArguments(objValue)) { + newValue = toPlainObject(objValue); + } + else if (!isObject(objValue) || (srcIndex && isFunction(objValue))) { + isCommon = false; + newValue = baseClone(srcValue, true); + } + else { + newValue = objValue; + } + } + else { + isCommon = false; + } + } + stack.set(srcValue, newValue); + + if (isCommon) { + // Recursively merge objects and arrays (susceptible to call stack limits). + mergeFunc(newValue, srcValue, srcIndex, customizer, stack); + } + assignMergeValue(object, key, newValue); + } + + /** + * The base implementation of `_.orderBy` without param guards. + * + * @private + * @param {Array|Object} collection The collection to iterate over. + * @param {Function[]|Object[]|string[]} iteratees The iteratees to sort by. + * @param {string[]} orders The sort orders of `iteratees`. + * @returns {Array} Returns the new sorted array. + */ + function baseOrderBy(collection, iteratees, orders) { + var index = -1, + toIteratee = getIteratee(); + + iteratees = arrayMap(iteratees.length ? iteratees : Array(1), function(iteratee) { + return toIteratee(iteratee); + }); + + var result = baseMap(collection, function(value, key, collection) { + var criteria = arrayMap(iteratees, function(iteratee) { + return iteratee(value); + }); + return { 'criteria': criteria, 'index': ++index, 'value': value }; + }); + + return baseSortBy(result, function(object, other) { + return compareMultiple(object, other, orders); + }); + } + + /** + * The base implementation of `_.pick` without support for individual + * property names. + * + * @private + * @param {Object} object The source object. + * @param {string[]} props The property names to pick. + * @returns {Object} Returns the new object. + */ + function basePick(object, props) { + object = Object(object); + return arrayReduce(props, function(result, key) { + if (key in object) { + result[key] = object[key]; + } + return result; + }, {}); + } + + /** + * The base implementation of `_.pickBy` without support for iteratee shorthands. + * + * @private + * @param {Object} object The source object. + * @param {Function} predicate The function invoked per property. + * @returns {Object} Returns the new object. + */ + function basePickBy(object, predicate) { + var result = {}; + baseForIn(object, function(value, key) { + if (predicate(value, key)) { + result[key] = value; + } + }); + return result; + } + + /** + * The base implementation of `_.property` without support for deep paths. + * + * @private + * @param {string} key The key of the property to get. + * @returns {Function} Returns the new function. + */ + function baseProperty(key) { + return function(object) { + return object == null ? undefined : object[key]; + }; + } + + /** + * A specialized version of `baseProperty` which supports deep paths. + * + * @private + * @param {Array|string} path The path of the property to get. + * @returns {Function} Returns the new function. + */ + function basePropertyDeep(path) { + return function(object) { + return baseGet(object, path); + }; + } + + /** + * The base implementation of `_.pullAll`. + * + * @private + * @param {Array} array The array to modify. + * @param {Array} values The values to remove. + * @returns {Array} Returns `array`. + */ + function basePullAll(array, values) { + return basePullAllBy(array, values); + } + + /** + * The base implementation of `_.pullAllBy` without support for iteratee + * shorthands. + * + * @private + * @param {Array} array The array to modify. + * @param {Array} values The values to remove. + * @param {Function} [iteratee] The iteratee invoked per element. + * @returns {Array} Returns `array`. + */ + function basePullAllBy(array, values, iteratee) { + var index = -1, + length = values.length, + seen = array; + + if (iteratee) { + seen = arrayMap(array, function(value) { return iteratee(value); }); + } + while (++index < length) { + var fromIndex = 0, + value = values[index], + computed = iteratee ? iteratee(value) : value; + + while ((fromIndex = baseIndexOf(seen, computed, fromIndex)) > -1) { + if (seen !== array) { + splice.call(seen, fromIndex, 1); + } + splice.call(array, fromIndex, 1); + } + } + return array; + } + + /** + * The base implementation of `_.pullAt` without support for individual + * indexes or capturing the removed elements. + * + * @private + * @param {Array} array The array to modify. + * @param {number[]} indexes The indexes of elements to remove. + * @returns {Array} Returns `array`. + */ + function basePullAt(array, indexes) { + var length = array ? indexes.length : 0, + lastIndex = length - 1; + + while (length--) { + var index = indexes[length]; + if (lastIndex == length || index != previous) { + var previous = index; + if (isIndex(index)) { + splice.call(array, index, 1); + } + else if (!isKey(index, array)) { + var path = baseCastPath(index), + object = parent(array, path); + + if (object != null) { + delete object[last(path)]; + } + } + else { + delete array[index]; + } + } + } + return array; + } + + /** + * The base implementation of `_.random` without support for returning + * floating-point numbers. + * + * @private + * @param {number} lower The lower bound. + * @param {number} upper The upper bound. + * @returns {number} Returns the random number. + */ + function baseRandom(lower, upper) { + return lower + nativeFloor(nativeRandom() * (upper - lower + 1)); + } + + /** + * The base implementation of `_.range` and `_.rangeRight` which doesn't + * coerce arguments to numbers. + * + * @private + * @param {number} start The start of the range. + * @param {number} end The end of the range. + * @param {number} step The value to increment or decrement by. + * @param {boolean} [fromRight] Specify iterating from right to left. + * @returns {Array} Returns the new array of numbers. + */ + function baseRange(start, end, step, fromRight) { + var index = -1, + length = nativeMax(nativeCeil((end - start) / (step || 1)), 0), + result = Array(length); + + while (length--) { + result[fromRight ? length : ++index] = start; + start += step; + } + return result; + } + + /** + * The base implementation of `_.set`. + * + * @private + * @param {Object} object The object to query. + * @param {Array|string} path The path of the property to set. + * @param {*} value The value to set. + * @param {Function} [customizer] The function to customize path creation. + * @returns {Object} Returns `object`. + */ + function baseSet(object, path, value, customizer) { + path = isKey(path, object) ? [path + ''] : baseCastPath(path); + + var index = -1, + length = path.length, + lastIndex = length - 1, + nested = object; + + while (nested != null && ++index < length) { + var key = path[index]; + if (isObject(nested)) { + var newValue = value; + if (index != lastIndex) { + var objValue = nested[key]; + newValue = customizer ? customizer(objValue, key, nested) : undefined; + if (newValue === undefined) { + newValue = objValue == null + ? (isIndex(path[index + 1]) ? [] : {}) + : objValue; + } + } + assignValue(nested, key, newValue); + } + nested = nested[key]; + } + return object; + } + + /** + * The base implementation of `setData` without support for hot loop detection. + * + * @private + * @param {Function} func The function to associate metadata with. + * @param {*} data The metadata. + * @returns {Function} Returns `func`. + */ + var baseSetData = !metaMap ? identity : function(func, data) { + metaMap.set(func, data); + return func; + }; + + /** + * The base implementation of `_.slice` without an iteratee call guard. + * + * @private + * @param {Array} array The array to slice. + * @param {number} [start=0] The start position. + * @param {number} [end=array.length] The end position. + * @returns {Array} Returns the slice of `array`. + */ + function baseSlice(array, start, end) { + var index = -1, + length = array.length; + + if (start < 0) { + start = -start > length ? 0 : (length + start); + } + end = end > length ? length : end; + if (end < 0) { + end += length; + } + length = start > end ? 0 : ((end - start) >>> 0); + start >>>= 0; + + var result = Array(length); + while (++index < length) { + result[index] = array[index + start]; + } + return result; + } + + /** + * The base implementation of `_.some` without support for iteratee shorthands. + * + * @private + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} predicate The function invoked per iteration. + * @returns {boolean} Returns `true` if any element passes the predicate check, else `false`. + */ + function baseSome(collection, predicate) { + var result; + + baseEach(collection, function(value, index, collection) { + result = predicate(value, index, collection); + return !result; + }); + return !!result; + } + + /** + * The base implementation of `_.sortedIndex` and `_.sortedLastIndex` which + * performs a binary search of `array` to determine the index at which `value` + * should be inserted into `array` in order to maintain its sort order. + * + * @private + * @param {Array} array The sorted array to inspect. + * @param {*} value The value to evaluate. + * @param {boolean} [retHighest] Specify returning the highest qualified index. + * @returns {number} Returns the index at which `value` should be inserted + * into `array`. + */ + function baseSortedIndex(array, value, retHighest) { + var low = 0, + high = array ? array.length : low; + + if (typeof value == 'number' && value === value && high <= HALF_MAX_ARRAY_LENGTH) { + while (low < high) { + var mid = (low + high) >>> 1, + computed = array[mid]; + + if ((retHighest ? (computed <= value) : (computed < value)) && computed !== null) { + low = mid + 1; + } else { + high = mid; + } + } + return high; + } + return baseSortedIndexBy(array, value, identity, retHighest); + } + + /** + * The base implementation of `_.sortedIndexBy` and `_.sortedLastIndexBy` + * which invokes `iteratee` for `value` and each element of `array` to compute + * their sort ranking. The iteratee is invoked with one argument; (value). + * + * @private + * @param {Array} array The sorted array to inspect. + * @param {*} value The value to evaluate. + * @param {Function} iteratee The iteratee invoked per element. + * @param {boolean} [retHighest] Specify returning the highest qualified index. + * @returns {number} Returns the index at which `value` should be inserted into `array`. + */ + function baseSortedIndexBy(array, value, iteratee, retHighest) { + value = iteratee(value); + + var low = 0, + high = array ? array.length : 0, + valIsNaN = value !== value, + valIsNull = value === null, + valIsUndef = value === undefined; + + while (low < high) { + var mid = nativeFloor((low + high) / 2), + computed = iteratee(array[mid]), + isDef = computed !== undefined, + isReflexive = computed === computed; + + if (valIsNaN) { + var setLow = isReflexive || retHighest; + } else if (valIsNull) { + setLow = isReflexive && isDef && (retHighest || computed != null); + } else if (valIsUndef) { + setLow = isReflexive && (retHighest || isDef); + } else if (computed == null) { + setLow = false; + } else { + setLow = retHighest ? (computed <= value) : (computed < value); + } + if (setLow) { + low = mid + 1; + } else { + high = mid; + } + } + return nativeMin(high, MAX_ARRAY_INDEX); + } + + /** + * The base implementation of `_.sortedUniq`. + * + * @private + * @param {Array} array The array to inspect. + * @returns {Array} Returns the new duplicate free array. + */ + function baseSortedUniq(array) { + return baseSortedUniqBy(array); + } + + /** + * The base implementation of `_.sortedUniqBy` without support for iteratee + * shorthands. + * + * @private + * @param {Array} array The array to inspect. + * @param {Function} [iteratee] The iteratee invoked per element. + * @returns {Array} Returns the new duplicate free array. + */ + function baseSortedUniqBy(array, iteratee) { + var index = 0, + length = array.length, + value = array[0], + computed = iteratee ? iteratee(value) : value, + seen = computed, + resIndex = 0, + result = [value]; + + while (++index < length) { + value = array[index], + computed = iteratee ? iteratee(value) : value; + + if (!eq(computed, seen)) { + seen = computed; + result[++resIndex] = value; + } + } + return result; + } + + /** + * The base implementation of `_.uniqBy` without support for iteratee shorthands. + * + * @private + * @param {Array} array The array to inspect. + * @param {Function} [iteratee] The iteratee invoked per element. + * @param {Function} [comparator] The comparator invoked per element. + * @returns {Array} Returns the new duplicate free array. + */ + function baseUniq(array, iteratee, comparator) { + var index = -1, + includes = arrayIncludes, + length = array.length, + isCommon = true, + result = [], + seen = result; + + if (comparator) { + isCommon = false; + includes = arrayIncludesWith; + } + else if (length >= LARGE_ARRAY_SIZE) { + var set = iteratee ? null : createSet(array); + if (set) { + return setToArray(set); + } + isCommon = false; + includes = cacheHas; + seen = new SetCache; + } + else { + seen = iteratee ? [] : result; + } + outer: + while (++index < length) { + var value = array[index], + computed = iteratee ? iteratee(value) : value; + + if (isCommon && computed === computed) { + var seenIndex = seen.length; + while (seenIndex--) { + if (seen[seenIndex] === computed) { + continue outer; + } + } + if (iteratee) { + seen.push(computed); + } + result.push(value); + } + else if (!includes(seen, computed, comparator)) { + if (seen !== result) { + seen.push(computed); + } + result.push(value); + } + } + return result; + } + + /** + * The base implementation of `_.unset`. + * + * @private + * @param {Object} object The object to modify. + * @param {Array|string} path The path of the property to unset. + * @returns {boolean} Returns `true` if the property is deleted, else `false`. + */ + function baseUnset(object, path) { + path = isKey(path, object) ? [path + ''] : baseCastPath(path); + object = parent(object, path); + var key = last(path); + return (object != null && has(object, key)) ? delete object[key] : true; + } + + /** + * The base implementation of methods like `_.dropWhile` and `_.takeWhile` + * without support for iteratee shorthands. + * + * @private + * @param {Array} array The array to query. + * @param {Function} predicate The function invoked per iteration. + * @param {boolean} [isDrop] Specify dropping elements instead of taking them. + * @param {boolean} [fromRight] Specify iterating from right to left. + * @returns {Array} Returns the slice of `array`. + */ + function baseWhile(array, predicate, isDrop, fromRight) { + var length = array.length, + index = fromRight ? length : -1; + + while ((fromRight ? index-- : ++index < length) && + predicate(array[index], index, array)) {} + + return isDrop + ? baseSlice(array, (fromRight ? 0 : index), (fromRight ? index + 1 : length)) + : baseSlice(array, (fromRight ? index + 1 : 0), (fromRight ? length : index)); + } + + /** + * The base implementation of `wrapperValue` which returns the result of + * performing a sequence of actions on the unwrapped `value`, where each + * successive action is supplied the return value of the previous. + * + * @private + * @param {*} value The unwrapped value. + * @param {Array} actions Actions to perform to resolve the unwrapped value. + * @returns {*} Returns the resolved value. + */ + function baseWrapperValue(value, actions) { + var result = value; + if (result instanceof LazyWrapper) { + result = result.value(); + } + return arrayReduce(actions, function(result, action) { + return action.func.apply(action.thisArg, arrayPush([result], action.args)); + }, result); + } + + /** + * The base implementation of methods like `_.xor`, without support for + * iteratee shorthands, that accepts an array of arrays to inspect. + * + * @private + * @param {Array} arrays The arrays to inspect. + * @param {Function} [iteratee] The iteratee invoked per element. + * @param {Function} [comparator] The comparator invoked per element. + * @returns {Array} Returns the new array of values. + */ + function baseXor(arrays, iteratee, comparator) { + var index = -1, + length = arrays.length; + + while (++index < length) { + var result = result + ? arrayPush( + baseDifference(result, arrays[index], iteratee, comparator), + baseDifference(arrays[index], result, iteratee, comparator) + ) + : arrays[index]; + } + return (result && result.length) ? baseUniq(result, iteratee, comparator) : []; + } + + /** + * This base implementation of `_.zipObject` which assigns values using `assignFunc`. + * + * @private + * @param {Array} props The property names. + * @param {Array} values The property values. + * @param {Function} assignFunc The function to assign values. + * @returns {Object} Returns the new object. + */ + function baseZipObject(props, values, assignFunc) { + var index = -1, + length = props.length, + valsLength = values.length, + result = {}; + + while (++index < length) { + assignFunc(result, props[index], index < valsLength ? values[index] : undefined); + } + return result; + } + + /** + * Creates a clone of `buffer`. + * + * @private + * @param {Buffer} buffer The buffer to clone. + * @param {boolean} [isDeep] Specify a deep clone. + * @returns {Buffer} Returns the cloned buffer. + */ + function cloneBuffer(buffer, isDeep) { + if (isDeep) { + return buffer.slice(); + } + var Ctor = buffer.constructor, + result = new Ctor(buffer.length); + + buffer.copy(result); + return result; + } + + /** + * Creates a clone of `arrayBuffer`. + * + * @private + * @param {ArrayBuffer} arrayBuffer The array buffer to clone. + * @returns {ArrayBuffer} Returns the cloned array buffer. + */ + function cloneArrayBuffer(arrayBuffer) { + var Ctor = arrayBuffer.constructor, + result = new Ctor(arrayBuffer.byteLength), + view = new Uint8Array(result); + + view.set(new Uint8Array(arrayBuffer)); + return result; + } + + /** + * Creates a clone of `map`. + * + * @private + * @param {Object} map The map to clone. + * @returns {Object} Returns the cloned map. + */ + function cloneMap(map) { + var Ctor = map.constructor; + return arrayReduce(mapToArray(map), addMapEntry, new Ctor); + } + + /** + * Creates a clone of `regexp`. + * + * @private + * @param {Object} regexp The regexp to clone. + * @returns {Object} Returns the cloned regexp. + */ + function cloneRegExp(regexp) { + var Ctor = regexp.constructor, + result = new Ctor(regexp.source, reFlags.exec(regexp)); + + result.lastIndex = regexp.lastIndex; + return result; + } + + /** + * Creates a clone of `set`. + * + * @private + * @param {Object} set The set to clone. + * @returns {Object} Returns the cloned set. + */ + function cloneSet(set) { + var Ctor = set.constructor; + return arrayReduce(setToArray(set), addSetEntry, new Ctor); + } + + /** + * Creates a clone of the `symbol` object. + * + * @private + * @param {Object} symbol The symbol object to clone. + * @returns {Object} Returns the cloned symbol object. + */ + function cloneSymbol(symbol) { + return Symbol ? Object(symbolValueOf.call(symbol)) : {}; + } + + /** + * Creates a clone of `typedArray`. + * + * @private + * @param {Object} typedArray The typed array to clone. + * @param {boolean} [isDeep] Specify a deep clone. + * @returns {Object} Returns the cloned typed array. + */ + function cloneTypedArray(typedArray, isDeep) { + var arrayBuffer = typedArray.buffer, + buffer = isDeep ? cloneArrayBuffer(arrayBuffer) : arrayBuffer, + Ctor = typedArray.constructor; + + return new Ctor(buffer, typedArray.byteOffset, typedArray.length); + } + + /** + * Creates an array that is the composition of partially applied arguments, + * placeholders, and provided arguments into a single array of arguments. + * + * @private + * @param {Array|Object} args The provided arguments. + * @param {Array} partials The arguments to prepend to those provided. + * @param {Array} holders The `partials` placeholder indexes. + * @params {boolean} [isCurried] Specify composing for a curried function. + * @returns {Array} Returns the new array of composed arguments. + */ + function composeArgs(args, partials, holders, isCurried) { + var argsIndex = -1, + argsLength = args.length, + holdersLength = holders.length, + leftIndex = -1, + leftLength = partials.length, + rangeLength = nativeMax(argsLength - holdersLength, 0), + result = Array(leftLength + rangeLength), + isUncurried = !isCurried; + + while (++leftIndex < leftLength) { + result[leftIndex] = partials[leftIndex]; + } + while (++argsIndex < holdersLength) { + if (isUncurried || argsIndex < argsLength) { + result[holders[argsIndex]] = args[argsIndex]; + } + } + while (rangeLength--) { + result[leftIndex++] = args[argsIndex++]; + } + return result; + } + + /** + * This function is like `composeArgs` except that the arguments composition + * is tailored for `_.partialRight`. + * + * @private + * @param {Array|Object} args The provided arguments. + * @param {Array} partials The arguments to append to those provided. + * @param {Array} holders The `partials` placeholder indexes. + * @params {boolean} [isCurried] Specify composing for a curried function. + * @returns {Array} Returns the new array of composed arguments. + */ + function composeArgsRight(args, partials, holders, isCurried) { + var argsIndex = -1, + argsLength = args.length, + holdersIndex = -1, + holdersLength = holders.length, + rightIndex = -1, + rightLength = partials.length, + rangeLength = nativeMax(argsLength - holdersLength, 0), + result = Array(rangeLength + rightLength), + isUncurried = !isCurried; + + while (++argsIndex < rangeLength) { + result[argsIndex] = args[argsIndex]; + } + var offset = argsIndex; + while (++rightIndex < rightLength) { + result[offset + rightIndex] = partials[rightIndex]; + } + while (++holdersIndex < holdersLength) { + if (isUncurried || argsIndex < argsLength) { + result[offset + holders[holdersIndex]] = args[argsIndex++]; + } + } + return result; + } + + /** + * Copies the values of `source` to `array`. + * + * @private + * @param {Array} source The array to copy values from. + * @param {Array} [array=[]] The array to copy values to. + * @returns {Array} Returns `array`. + */ + function copyArray(source, array) { + var index = -1, + length = source.length; + + array || (array = Array(length)); + while (++index < length) { + array[index] = source[index]; + } + return array; + } + + /** + * Copies properties of `source` to `object`. + * + * @private + * @param {Object} source The object to copy properties from. + * @param {Array} props The property names to copy. + * @param {Object} [object={}] The object to copy properties to. + * @returns {Object} Returns `object`. + */ + function copyObject(source, props, object) { + return copyObjectWith(source, props, object); + } + + /** + * This function is like `copyObject` except that it accepts a function to + * customize copied values. + * + * @private + * @param {Object} source The object to copy properties from. + * @param {Array} props The property names to copy. + * @param {Object} [object={}] The object to copy properties to. + * @param {Function} [customizer] The function to customize copied values. + * @returns {Object} Returns `object`. + */ + function copyObjectWith(source, props, object, customizer) { + object || (object = {}); + + var index = -1, + length = props.length; + + while (++index < length) { + var key = props[index]; + + var newValue = customizer + ? customizer(object[key], source[key], key, object, source) + : source[key]; + + assignValue(object, key, newValue); + } + return object; + } + + /** + * Copies own symbol properties of `source` to `object`. + * + * @private + * @param {Object} source The object to copy symbols from. + * @param {Object} [object={}] The object to copy symbols to. + * @returns {Object} Returns `object`. + */ + function copySymbols(source, object) { + return copyObject(source, getSymbols(source), object); + } + + /** + * Creates a function like `_.groupBy`. + * + * @private + * @param {Function} setter The function to set accumulator values. + * @param {Function} [initializer] The accumulator object initializer. + * @returns {Function} Returns the new aggregator function. + */ + function createAggregator(setter, initializer) { + return function(collection, iteratee) { + var func = isArray(collection) ? arrayAggregator : baseAggregator, + accumulator = initializer ? initializer() : {}; + + return func(collection, setter, getIteratee(iteratee), accumulator); + }; + } + + /** + * Creates a function like `_.assign`. + * + * @private + * @param {Function} assigner The function to assign values. + * @returns {Function} Returns the new assigner function. + */ + function createAssigner(assigner) { + return rest(function(object, sources) { + var index = -1, + length = sources.length, + customizer = length > 1 ? sources[length - 1] : undefined, + guard = length > 2 ? sources[2] : undefined; + + customizer = typeof customizer == 'function' + ? (length--, customizer) + : undefined; + + if (guard && isIterateeCall(sources[0], sources[1], guard)) { + customizer = length < 3 ? undefined : customizer; + length = 1; + } + object = Object(object); + while (++index < length) { + var source = sources[index]; + if (source) { + assigner(object, source, index, customizer); + } + } + return object; + }); + } + + /** + * Creates a `baseEach` or `baseEachRight` function. + * + * @private + * @param {Function} eachFunc The function to iterate over a collection. + * @param {boolean} [fromRight] Specify iterating from right to left. + * @returns {Function} Returns the new base function. + */ + function createBaseEach(eachFunc, fromRight) { + return function(collection, iteratee) { + if (collection == null) { + return collection; + } + if (!isArrayLike(collection)) { + return eachFunc(collection, iteratee); + } + var length = collection.length, + index = fromRight ? length : -1, + iterable = Object(collection); + + while ((fromRight ? index-- : ++index < length)) { + if (iteratee(iterable[index], index, iterable) === false) { + break; + } + } + return collection; + }; + } + + /** + * Creates a base function for methods like `_.forIn`. + * + * @private + * @param {boolean} [fromRight] Specify iterating from right to left. + * @returns {Function} Returns the new base function. + */ + function createBaseFor(fromRight) { + return function(object, iteratee, keysFunc) { + var index = -1, + iterable = Object(object), + props = keysFunc(object), + length = props.length; + + while (length--) { + var key = props[fromRight ? length : ++index]; + if (iteratee(iterable[key], key, iterable) === false) { + break; + } + } + return object; + }; + } + + /** + * Creates a function that wraps `func` to invoke it with the optional `this` + * binding of `thisArg`. + * + * @private + * @param {Function} func The function to wrap. + * @param {number} bitmask The bitmask of wrapper flags. See `createWrapper` for more details. + * @param {*} [thisArg] The `this` binding of `func`. + * @returns {Function} Returns the new wrapped function. + */ + function createBaseWrapper(func, bitmask, thisArg) { + var isBind = bitmask & BIND_FLAG, + Ctor = createCtorWrapper(func); + + function wrapper() { + var fn = (this && this !== root && this instanceof wrapper) ? Ctor : func; + return fn.apply(isBind ? thisArg : this, arguments); + } + return wrapper; + } + + /** + * Creates a function like `_.lowerFirst`. + * + * @private + * @param {string} methodName The name of the `String` case method to use. + * @returns {Function} Returns the new function. + */ + function createCaseFirst(methodName) { + return function(string) { + string = toString(string); + + var strSymbols = reHasComplexSymbol.test(string) + ? stringToArray(string) + : undefined; + + var chr = strSymbols ? strSymbols[0] : string.charAt(0), + trailing = strSymbols ? strSymbols.slice(1).join('') : string.slice(1); + + return chr[methodName]() + trailing; + }; + } + + /** + * Creates a function like `_.camelCase`. + * + * @private + * @param {Function} callback The function to combine each word. + * @returns {Function} Returns the new compounder function. + */ + function createCompounder(callback) { + return function(string) { + return arrayReduce(words(deburr(string)), callback, ''); + }; + } + + /** + * Creates a function that produces an instance of `Ctor` regardless of + * whether it was invoked as part of a `new` expression or by `call` or `apply`. + * + * @private + * @param {Function} Ctor The constructor to wrap. + * @returns {Function} Returns the new wrapped function. + */ + function createCtorWrapper(Ctor) { + return function() { + // Use a `switch` statement to work with class constructors. + // See http://ecma-international.org/ecma-262/6.0/#sec-ecmascript-function-objects-call-thisargument-argumentslist + // for more details. + var args = arguments; + switch (args.length) { + case 0: return new Ctor; + case 1: return new Ctor(args[0]); + case 2: return new Ctor(args[0], args[1]); + case 3: return new Ctor(args[0], args[1], args[2]); + case 4: return new Ctor(args[0], args[1], args[2], args[3]); + case 5: return new Ctor(args[0], args[1], args[2], args[3], args[4]); + case 6: return new Ctor(args[0], args[1], args[2], args[3], args[4], args[5]); + case 7: return new Ctor(args[0], args[1], args[2], args[3], args[4], args[5], args[6]); + } + var thisBinding = baseCreate(Ctor.prototype), + result = Ctor.apply(thisBinding, args); + + // Mimic the constructor's `return` behavior. + // See https://es5.github.io/#x13.2.2 for more details. + return isObject(result) ? result : thisBinding; + }; + } + + /** + * Creates a function that wraps `func` to enable currying. + * + * @private + * @param {Function} func The function to wrap. + * @param {number} bitmask The bitmask of wrapper flags. See `createWrapper` for more details. + * @param {number} arity The arity of `func`. + * @returns {Function} Returns the new wrapped function. + */ + function createCurryWrapper(func, bitmask, arity) { + var Ctor = createCtorWrapper(func); + + function wrapper() { + var length = arguments.length, + args = Array(length), + index = length, + placeholder = getPlaceholder(wrapper); + + while (index--) { + args[index] = arguments[index]; + } + var holders = (length < 3 && args[0] !== placeholder && args[length - 1] !== placeholder) + ? [] + : replaceHolders(args, placeholder); + + length -= holders.length; + if (length < arity) { + return createRecurryWrapper( + func, bitmask, createHybridWrapper, wrapper.placeholder, undefined, + args, holders, undefined, undefined, arity - length); + } + var fn = (this && this !== root && this instanceof wrapper) ? Ctor : func; + return apply(fn, this, args); + } + return wrapper; + } + + /** + * Creates a `_.flow` or `_.flowRight` function. + * + * @private + * @param {boolean} [fromRight] Specify iterating from right to left. + * @returns {Function} Returns the new flow function. + */ + function createFlow(fromRight) { + return rest(function(funcs) { + funcs = baseFlatten(funcs, 1); + + var length = funcs.length, + index = length, + prereq = LodashWrapper.prototype.thru; + + if (fromRight) { + funcs.reverse(); + } + while (index--) { + var func = funcs[index]; + if (typeof func != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + if (prereq && !wrapper && getFuncName(func) == 'wrapper') { + var wrapper = new LodashWrapper([], true); + } + } + index = wrapper ? index : length; + while (++index < length) { + func = funcs[index]; + + var funcName = getFuncName(func), + data = funcName == 'wrapper' ? getData(func) : undefined; + + if (data && isLaziable(data[0]) && + data[1] == (ARY_FLAG | CURRY_FLAG | PARTIAL_FLAG | REARG_FLAG) && + !data[4].length && data[9] == 1 + ) { + wrapper = wrapper[getFuncName(data[0])].apply(wrapper, data[3]); + } else { + wrapper = (func.length == 1 && isLaziable(func)) ? wrapper[funcName]() : wrapper.thru(func); + } + } + return function() { + var args = arguments, + value = args[0]; + + if (wrapper && args.length == 1 && + isArray(value) && value.length >= LARGE_ARRAY_SIZE) { + return wrapper.plant(value).value(); + } + var index = 0, + result = length ? funcs[index].apply(this, args) : value; + + while (++index < length) { + result = funcs[index].call(this, result); + } + return result; + }; + }); + } + + /** + * Creates a function that wraps `func` to invoke it with optional `this` + * binding of `thisArg`, partial application, and currying. + * + * @private + * @param {Function|string} func The function or method name to wrap. + * @param {number} bitmask The bitmask of wrapper flags. See `createWrapper` for more details. + * @param {*} [thisArg] The `this` binding of `func`. + * @param {Array} [partials] The arguments to prepend to those provided to the new function. + * @param {Array} [holders] The `partials` placeholder indexes. + * @param {Array} [partialsRight] The arguments to append to those provided to the new function. + * @param {Array} [holdersRight] The `partialsRight` placeholder indexes. + * @param {Array} [argPos] The argument positions of the new function. + * @param {number} [ary] The arity cap of `func`. + * @param {number} [arity] The arity of `func`. + * @returns {Function} Returns the new wrapped function. + */ + function createHybridWrapper(func, bitmask, thisArg, partials, holders, partialsRight, holdersRight, argPos, ary, arity) { + var isAry = bitmask & ARY_FLAG, + isBind = bitmask & BIND_FLAG, + isBindKey = bitmask & BIND_KEY_FLAG, + isCurried = bitmask & (CURRY_FLAG | CURRY_RIGHT_FLAG), + isFlip = bitmask & FLIP_FLAG, + Ctor = isBindKey ? undefined : createCtorWrapper(func); + + function wrapper() { + var length = arguments.length, + index = length, + args = Array(length); + + while (index--) { + args[index] = arguments[index]; + } + if (isCurried) { + var placeholder = getPlaceholder(wrapper), + holdersCount = countHolders(args, placeholder); + } + if (partials) { + args = composeArgs(args, partials, holders, isCurried); + } + if (partialsRight) { + args = composeArgsRight(args, partialsRight, holdersRight, isCurried); + } + length -= holdersCount; + if (isCurried && length < arity) { + var newHolders = replaceHolders(args, placeholder); + return createRecurryWrapper( + func, bitmask, createHybridWrapper, wrapper.placeholder, thisArg, + args, newHolders, argPos, ary, arity - length + ); + } + var thisBinding = isBind ? thisArg : this, + fn = isBindKey ? thisBinding[func] : func; + + length = args.length; + if (argPos) { + args = reorder(args, argPos); + } else if (isFlip && length > 1) { + args.reverse(); + } + if (isAry && ary < length) { + args.length = ary; + } + if (this && this !== root && this instanceof wrapper) { + fn = Ctor || createCtorWrapper(fn); + } + return fn.apply(thisBinding, args); + } + return wrapper; + } + + /** + * Creates a function like `_.invertBy`. + * + * @private + * @param {Function} setter The function to set accumulator values. + * @param {Function} toIteratee The function to resolve iteratees. + * @returns {Function} Returns the new inverter function. + */ + function createInverter(setter, toIteratee) { + return function(object, iteratee) { + return baseInverter(object, setter, toIteratee(iteratee), {}); + }; + } + + /** + * Creates a function like `_.over`. + * + * @private + * @param {Function} arrayFunc The function to iterate over iteratees. + * @returns {Function} Returns the new invoker function. + */ + function createOver(arrayFunc) { + return rest(function(iteratees) { + iteratees = arrayMap(baseFlatten(iteratees, 1), getIteratee()); + return rest(function(args) { + var thisArg = this; + return arrayFunc(iteratees, function(iteratee) { + return apply(iteratee, thisArg, args); + }); + }); + }); + } + + /** + * Creates the padding for `string` based on `length`. The `chars` string + * is truncated if the number of characters exceeds `length`. + * + * @private + * @param {string} string The string to create padding for. + * @param {number} [length=0] The padding length. + * @param {string} [chars=' '] The string used as padding. + * @returns {string} Returns the padding for `string`. + */ + function createPadding(string, length, chars) { + length = toInteger(length); + + var strLength = stringSize(string); + if (!length || strLength >= length) { + return ''; + } + var padLength = length - strLength; + chars = chars === undefined ? ' ' : (chars + ''); + + var result = repeat(chars, nativeCeil(padLength / stringSize(chars))); + return reHasComplexSymbol.test(chars) + ? stringToArray(result).slice(0, padLength).join('') + : result.slice(0, padLength); + } + + /** + * Creates a function that wraps `func` to invoke it with the optional `this` + * binding of `thisArg` and the `partials` prepended to those provided to + * the wrapper. + * + * @private + * @param {Function} func The function to wrap. + * @param {number} bitmask The bitmask of wrapper flags. See `createWrapper` for more details. + * @param {*} thisArg The `this` binding of `func`. + * @param {Array} partials The arguments to prepend to those provided to the new function. + * @returns {Function} Returns the new wrapped function. + */ + function createPartialWrapper(func, bitmask, thisArg, partials) { + var isBind = bitmask & BIND_FLAG, + Ctor = createCtorWrapper(func); + + function wrapper() { + var argsIndex = -1, + argsLength = arguments.length, + leftIndex = -1, + leftLength = partials.length, + args = Array(leftLength + argsLength), + fn = (this && this !== root && this instanceof wrapper) ? Ctor : func; + + while (++leftIndex < leftLength) { + args[leftIndex] = partials[leftIndex]; + } + while (argsLength--) { + args[leftIndex++] = arguments[++argsIndex]; + } + return apply(fn, isBind ? thisArg : this, args); + } + return wrapper; + } + + /** + * Creates a `_.range` or `_.rangeRight` function. + * + * @private + * @param {boolean} [fromRight] Specify iterating from right to left. + * @returns {Function} Returns the new range function. + */ + function createRange(fromRight) { + return function(start, end, step) { + if (step && typeof step != 'number' && isIterateeCall(start, end, step)) { + end = step = undefined; + } + // Ensure the sign of `-0` is preserved. + start = toNumber(start); + start = start === start ? start : 0; + if (end === undefined) { + end = start; + start = 0; + } else { + end = toNumber(end) || 0; + } + step = step === undefined ? (start < end ? 1 : -1) : (toNumber(step) || 0); + return baseRange(start, end, step, fromRight); + }; + } + + /** + * Creates a function that wraps `func` to continue currying. + * + * @private + * @param {Function} func The function to wrap. + * @param {number} bitmask The bitmask of wrapper flags. See `createWrapper` for more details. + * @param {Function} wrapFunc The function to create the `func` wrapper. + * @param {*} placeholder The placeholder value. + * @param {*} [thisArg] The `this` binding of `func`. + * @param {Array} [partials] The arguments to prepend to those provided to the new function. + * @param {Array} [holders] The `partials` placeholder indexes. + * @param {Array} [argPos] The argument positions of the new function. + * @param {number} [ary] The arity cap of `func`. + * @param {number} [arity] The arity of `func`. + * @returns {Function} Returns the new wrapped function. + */ + function createRecurryWrapper(func, bitmask, wrapFunc, placeholder, thisArg, partials, holders, argPos, ary, arity) { + var isCurry = bitmask & CURRY_FLAG, + newArgPos = argPos ? copyArray(argPos) : undefined, + newHolders = isCurry ? holders : undefined, + newHoldersRight = isCurry ? undefined : holders, + newPartials = isCurry ? partials : undefined, + newPartialsRight = isCurry ? undefined : partials; + + bitmask |= (isCurry ? PARTIAL_FLAG : PARTIAL_RIGHT_FLAG); + bitmask &= ~(isCurry ? PARTIAL_RIGHT_FLAG : PARTIAL_FLAG); + + if (!(bitmask & CURRY_BOUND_FLAG)) { + bitmask &= ~(BIND_FLAG | BIND_KEY_FLAG); + } + var newData = [ + func, bitmask, thisArg, newPartials, newHolders, newPartialsRight, + newHoldersRight, newArgPos, ary, arity + ]; + + var result = wrapFunc.apply(undefined, newData); + if (isLaziable(func)) { + setData(result, newData); + } + result.placeholder = placeholder; + return result; + } + + /** + * Creates a function like `_.round`. + * + * @private + * @param {string} methodName The name of the `Math` method to use when rounding. + * @returns {Function} Returns the new round function. + */ + function createRound(methodName) { + var func = Math[methodName]; + return function(number, precision) { + number = toNumber(number); + precision = toInteger(precision); + if (precision) { + // Shift with exponential notation to avoid floating-point issues. + // See [MDN](https://mdn.io/round#Examples) for more details. + var pair = (toString(number) + 'e').split('e'), + value = func(pair[0] + 'e' + (+pair[1] + precision)); + + pair = (toString(value) + 'e').split('e'); + return +(pair[0] + 'e' + (+pair[1] - precision)); + } + return func(number); + }; + } + + /** + * Creates a set of `values`. + * + * @private + * @param {Array} values The values to add to the set. + * @returns {Object} Returns the new set. + */ + var createSet = !(Set && new Set([1, 2]).size === 2) ? noop : function(values) { + return new Set(values); + }; + + /** + * Creates a function that either curries or invokes `func` with optional + * `this` binding and partially applied arguments. + * + * @private + * @param {Function|string} func The function or method name to wrap. + * @param {number} bitmask The bitmask of wrapper flags. + * The bitmask may be composed of the following flags: + * 1 - `_.bind` + * 2 - `_.bindKey` + * 4 - `_.curry` or `_.curryRight` of a bound function + * 8 - `_.curry` + * 16 - `_.curryRight` + * 32 - `_.partial` + * 64 - `_.partialRight` + * 128 - `_.rearg` + * 256 - `_.ary` + * @param {*} [thisArg] The `this` binding of `func`. + * @param {Array} [partials] The arguments to be partially applied. + * @param {Array} [holders] The `partials` placeholder indexes. + * @param {Array} [argPos] The argument positions of the new function. + * @param {number} [ary] The arity cap of `func`. + * @param {number} [arity] The arity of `func`. + * @returns {Function} Returns the new wrapped function. + */ + function createWrapper(func, bitmask, thisArg, partials, holders, argPos, ary, arity) { + var isBindKey = bitmask & BIND_KEY_FLAG; + if (!isBindKey && typeof func != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + var length = partials ? partials.length : 0; + if (!length) { + bitmask &= ~(PARTIAL_FLAG | PARTIAL_RIGHT_FLAG); + partials = holders = undefined; + } + ary = ary === undefined ? ary : nativeMax(toInteger(ary), 0); + arity = arity === undefined ? arity : toInteger(arity); + length -= holders ? holders.length : 0; + + if (bitmask & PARTIAL_RIGHT_FLAG) { + var partialsRight = partials, + holdersRight = holders; + + partials = holders = undefined; + } + var data = isBindKey ? undefined : getData(func); + + var newData = [ + func, bitmask, thisArg, partials, holders, partialsRight, holdersRight, + argPos, ary, arity + ]; + + if (data) { + mergeData(newData, data); + } + func = newData[0]; + bitmask = newData[1]; + thisArg = newData[2]; + partials = newData[3]; + holders = newData[4]; + arity = newData[9] = newData[9] == null + ? (isBindKey ? 0 : func.length) + : nativeMax(newData[9] - length, 0); + + if (!arity && bitmask & (CURRY_FLAG | CURRY_RIGHT_FLAG)) { + bitmask &= ~(CURRY_FLAG | CURRY_RIGHT_FLAG); + } + if (!bitmask || bitmask == BIND_FLAG) { + var result = createBaseWrapper(func, bitmask, thisArg); + } else if (bitmask == CURRY_FLAG || bitmask == CURRY_RIGHT_FLAG) { + result = createCurryWrapper(func, bitmask, arity); + } else if ((bitmask == PARTIAL_FLAG || bitmask == (BIND_FLAG | PARTIAL_FLAG)) && !holders.length) { + result = createPartialWrapper(func, bitmask, thisArg, partials); + } else { + result = createHybridWrapper.apply(undefined, newData); + } + var setter = data ? baseSetData : setData; + return setter(result, newData); + } + + /** + * A specialized version of `baseIsEqualDeep` for arrays with support for + * partial deep comparisons. + * + * @private + * @param {Array} array The array to compare. + * @param {Array} other The other array to compare. + * @param {Function} equalFunc The function to determine equivalents of values. + * @param {Function} [customizer] The function to customize comparisons. + * @param {number} [bitmask] The bitmask of comparison flags. See `baseIsEqual` for more details. + * @param {Object} [stack] Tracks traversed `array` and `other` objects. + * @returns {boolean} Returns `true` if the arrays are equivalent, else `false`. + */ + function equalArrays(array, other, equalFunc, customizer, bitmask, stack) { + var index = -1, + isPartial = bitmask & PARTIAL_COMPARE_FLAG, + isUnordered = bitmask & UNORDERED_COMPARE_FLAG, + arrLength = array.length, + othLength = other.length; + + if (arrLength != othLength && !(isPartial && othLength > arrLength)) { + return false; + } + // Assume cyclic values are equal. + var stacked = stack.get(array); + if (stacked) { + return stacked == other; + } + var result = true; + stack.set(array, other); + + // Ignore non-index properties. + while (++index < arrLength) { + var arrValue = array[index], + othValue = other[index]; + + if (customizer) { + var compared = isPartial + ? customizer(othValue, arrValue, index, other, array, stack) + : customizer(arrValue, othValue, index, array, other, stack); + } + if (compared !== undefined) { + if (compared) { + continue; + } + result = false; + break; + } + // Recursively compare arrays (susceptible to call stack limits). + if (isUnordered) { + if (!arraySome(other, function(othValue) { + return arrValue === othValue || equalFunc(arrValue, othValue, customizer, bitmask, stack); + })) { + result = false; + break; + } + } else if (!(arrValue === othValue || equalFunc(arrValue, othValue, customizer, bitmask, stack))) { + result = false; + break; + } + } + stack['delete'](array); + return result; + } + + /** + * A specialized version of `baseIsEqualDeep` for comparing objects of + * the same `toStringTag`. + * + * **Note:** This function only supports comparing values with tags of + * `Boolean`, `Date`, `Error`, `Number`, `RegExp`, or `String`. + * + * @private + * @param {Object} object The object to compare. + * @param {Object} other The other object to compare. + * @param {string} tag The `toStringTag` of the objects to compare. + * @param {Function} equalFunc The function to determine equivalents of values. + * @param {Function} [customizer] The function to customize comparisons. + * @param {number} [bitmask] The bitmask of comparison flags. See `baseIsEqual` for more details. + * @returns {boolean} Returns `true` if the objects are equivalent, else `false`. + */ + function equalByTag(object, other, tag, equalFunc, customizer, bitmask) { + switch (tag) { + case arrayBufferTag: + if ((object.byteLength != other.byteLength) || + !equalFunc(new Uint8Array(object), new Uint8Array(other))) { + return false; + } + return true; + + case boolTag: + case dateTag: + // Coerce dates and booleans to numbers, dates to milliseconds and booleans + // to `1` or `0` treating invalid dates coerced to `NaN` as not equal. + return +object == +other; + + case errorTag: + return object.name == other.name && object.message == other.message; + + case numberTag: + // Treat `NaN` vs. `NaN` as equal. + return (object != +object) ? other != +other : object == +other; + + case regexpTag: + case stringTag: + // Coerce regexes to strings and treat strings primitives and string + // objects as equal. See https://es5.github.io/#x15.10.6.4 for more details. + return object == (other + ''); + + case mapTag: + var convert = mapToArray; + + case setTag: + var isPartial = bitmask & PARTIAL_COMPARE_FLAG; + convert || (convert = setToArray); + + // Recursively compare objects (susceptible to call stack limits). + return (isPartial || object.size == other.size) && + equalFunc(convert(object), convert(other), customizer, bitmask | UNORDERED_COMPARE_FLAG); + + case symbolTag: + return !!Symbol && (symbolValueOf.call(object) == symbolValueOf.call(other)); + } + return false; + } + + /** + * A specialized version of `baseIsEqualDeep` for objects with support for + * partial deep comparisons. + * + * @private + * @param {Object} object The object to compare. + * @param {Object} other The other object to compare. + * @param {Function} equalFunc The function to determine equivalents of values. + * @param {Function} [customizer] The function to customize comparisons. + * @param {number} [bitmask] The bitmask of comparison flags. See `baseIsEqual` for more details. + * @param {Object} [stack] Tracks traversed `object` and `other` objects. + * @returns {boolean} Returns `true` if the objects are equivalent, else `false`. + */ + function equalObjects(object, other, equalFunc, customizer, bitmask, stack) { + var isPartial = bitmask & PARTIAL_COMPARE_FLAG, + objProps = keys(object), + objLength = objProps.length, + othProps = keys(other), + othLength = othProps.length; + + if (objLength != othLength && !isPartial) { + return false; + } + var index = objLength; + while (index--) { + var key = objProps[index]; + if (!(isPartial ? key in other : baseHas(other, key))) { + return false; + } + } + // Assume cyclic values are equal. + var stacked = stack.get(object); + if (stacked) { + return stacked == other; + } + var result = true; + stack.set(object, other); + + var skipCtor = isPartial; + while (++index < objLength) { + key = objProps[index]; + var objValue = object[key], + othValue = other[key]; + + if (customizer) { + var compared = isPartial + ? customizer(othValue, objValue, key, other, object, stack) + : customizer(objValue, othValue, key, object, other, stack); + } + // Recursively compare objects (susceptible to call stack limits). + if (!(compared === undefined + ? (objValue === othValue || equalFunc(objValue, othValue, customizer, bitmask, stack)) + : compared + )) { + result = false; + break; + } + skipCtor || (skipCtor = key == 'constructor'); + } + if (result && !skipCtor) { + var objCtor = object.constructor, + othCtor = other.constructor; + + // Non `Object` object instances with different constructors are not equal. + if (objCtor != othCtor && + ('constructor' in object && 'constructor' in other) && + !(typeof objCtor == 'function' && objCtor instanceof objCtor && + typeof othCtor == 'function' && othCtor instanceof othCtor)) { + result = false; + } + } + stack['delete'](object); + return result; + } + + /** + * Gets metadata for `func`. + * + * @private + * @param {Function} func The function to query. + * @returns {*} Returns the metadata for `func`. + */ + var getData = !metaMap ? noop : function(func) { + return metaMap.get(func); + }; + + /** + * Gets the name of `func`. + * + * @private + * @param {Function} func The function to query. + * @returns {string} Returns the function name. + */ + function getFuncName(func) { + var result = (func.name + ''), + array = realNames[result], + length = hasOwnProperty.call(realNames, result) ? array.length : 0; + + while (length--) { + var data = array[length], + otherFunc = data.func; + if (otherFunc == null || otherFunc == func) { + return data.name; + } + } + return result; + } + + /** + * Gets the appropriate "iteratee" function. If the `_.iteratee` method is + * customized this function returns the custom method, otherwise it returns + * `baseIteratee`. If arguments are provided the chosen function is invoked + * with them and its result is returned. + * + * @private + * @param {*} [value] The value to convert to an iteratee. + * @param {number} [arity] The arity of the created iteratee. + * @returns {Function} Returns the chosen function or its result. + */ + function getIteratee() { + var result = lodash.iteratee || iteratee; + result = result === iteratee ? baseIteratee : result; + return arguments.length ? result(arguments[0], arguments[1]) : result; + } + + /** + * Gets the "length" property value of `object`. + * + * **Note:** This function is used to avoid a [JIT bug](https://bugs.webkit.org/show_bug.cgi?id=142792) + * that affects Safari on at least iOS 8.1-8.3 ARM64. + * + * @private + * @param {Object} object The object to query. + * @returns {*} Returns the "length" value. + */ + var getLength = baseProperty('length'); + + /** + * Gets the property names, values, and compare flags of `object`. + * + * @private + * @param {Object} object The object to query. + * @returns {Array} Returns the match data of `object`. + */ + function getMatchData(object) { + var result = toPairs(object), + length = result.length; + + while (length--) { + result[length][2] = isStrictComparable(result[length][1]); + } + return result; + } + + /** + * Gets the native function at `key` of `object`. + * + * @private + * @param {Object} object The object to query. + * @param {string} key The key of the method to get. + * @returns {*} Returns the function if it's native, else `undefined`. + */ + function getNative(object, key) { + var value = object == null ? undefined : object[key]; + return isNative(value) ? value : undefined; + } + + /** + * Gets the argument placeholder value for `func`. + * + * @private + * @param {Function} func The function to inspect. + * @returns {*} Returns the placeholder value. + */ + function getPlaceholder(func) { + var object = hasOwnProperty.call(lodash, 'placeholder') ? lodash : func; + return object.placeholder; + } + + /** + * Creates an array of the own symbol properties of `object`. + * + * @private + * @param {Object} object The object to query. + * @returns {Array} Returns the array of symbols. + */ + var getSymbols = getOwnPropertySymbols || function() { + return []; + }; + + /** + * Gets the `toStringTag` of `value`. + * + * @private + * @param {*} value The value to query. + * @returns {string} Returns the `toStringTag`. + */ + function getTag(value) { + return objectToString.call(value); + } + + // Fallback for IE 11 providing `toStringTag` values for maps, sets, and weakmaps. + if ((Map && getTag(new Map) != mapTag) || + (Set && getTag(new Set) != setTag) || + (WeakMap && getTag(new WeakMap) != weakMapTag)) { + getTag = function(value) { + var result = objectToString.call(value), + Ctor = result == objectTag ? value.constructor : null, + ctorString = typeof Ctor == 'function' ? funcToString.call(Ctor) : ''; + + if (ctorString) { + switch (ctorString) { + case mapCtorString: return mapTag; + case setCtorString: return setTag; + case weakMapCtorString: return weakMapTag; + } + } + return result; + }; + } + + /** + * Gets the view, applying any `transforms` to the `start` and `end` positions. + * + * @private + * @param {number} start The start of the view. + * @param {number} end The end of the view. + * @param {Array} transforms The transformations to apply to the view. + * @returns {Object} Returns an object containing the `start` and `end` + * positions of the view. + */ + function getView(start, end, transforms) { + var index = -1, + length = transforms.length; + + while (++index < length) { + var data = transforms[index], + size = data.size; + + switch (data.type) { + case 'drop': start += size; break; + case 'dropRight': end -= size; break; + case 'take': end = nativeMin(end, start + size); break; + case 'takeRight': start = nativeMax(start, end - size); break; + } + } + return { 'start': start, 'end': end }; + } + + /** + * Checks if `path` exists on `object`. + * + * @private + * @param {Object} object The object to query. + * @param {Array|string} path The path to check. + * @param {Function} hasFunc The function to check properties. + * @returns {boolean} Returns `true` if `path` exists, else `false`. + */ + function hasPath(object, path, hasFunc) { + if (object == null) { + return false; + } + var result = hasFunc(object, path); + if (!result && !isKey(path)) { + path = baseCastPath(path); + object = parent(object, path); + if (object != null) { + path = last(path); + result = hasFunc(object, path); + } + } + var length = object ? object.length : undefined; + return result || ( + !!length && isLength(length) && isIndex(path, length) && + (isArray(object) || isString(object) || isArguments(object)) + ); + } + + /** + * Initializes an array clone. + * + * @private + * @param {Array} array The array to clone. + * @returns {Array} Returns the initialized clone. + */ + function initCloneArray(array) { + var length = array.length, + result = array.constructor(length); + + // Add properties assigned by `RegExp#exec`. + if (length && typeof array[0] == 'string' && hasOwnProperty.call(array, 'index')) { + result.index = array.index; + result.input = array.input; + } + return result; + } + + /** + * Initializes an object clone. + * + * @private + * @param {Object} object The object to clone. + * @returns {Object} Returns the initialized clone. + */ + function initCloneObject(object) { + return (isFunction(object.constructor) && !isPrototype(object)) + ? baseCreate(getPrototypeOf(object)) + : {}; + } + + /** + * Initializes an object clone based on its `toStringTag`. + * + * **Note:** This function only supports cloning values with tags of + * `Boolean`, `Date`, `Error`, `Number`, `RegExp`, or `String`. + * + * @private + * @param {Object} object The object to clone. + * @param {string} tag The `toStringTag` of the object to clone. + * @param {boolean} [isDeep] Specify a deep clone. + * @returns {Object} Returns the initialized clone. + */ + function initCloneByTag(object, tag, isDeep) { + var Ctor = object.constructor; + switch (tag) { + case arrayBufferTag: + return cloneArrayBuffer(object); + + case boolTag: + case dateTag: + return new Ctor(+object); + + case float32Tag: case float64Tag: + case int8Tag: case int16Tag: case int32Tag: + case uint8Tag: case uint8ClampedTag: case uint16Tag: case uint32Tag: + return cloneTypedArray(object, isDeep); + + case mapTag: + return cloneMap(object); + + case numberTag: + case stringTag: + return new Ctor(object); + + case regexpTag: + return cloneRegExp(object); + + case setTag: + return cloneSet(object); + + case symbolTag: + return cloneSymbol(object); + } + } + + /** + * Creates an array of index keys for `object` values of arrays, + * `arguments` objects, and strings, otherwise `null` is returned. + * + * @private + * @param {Object} object The object to query. + * @returns {Array|null} Returns index keys, else `null`. + */ + function indexKeys(object) { + var length = object ? object.length : undefined; + if (isLength(length) && + (isArray(object) || isString(object) || isArguments(object))) { + return baseTimes(length, String); + } + return null; + } + + /** + * Checks if the given arguments are from an iteratee call. + * + * @private + * @param {*} value The potential iteratee value argument. + * @param {*} index The potential iteratee index or key argument. + * @param {*} object The potential iteratee object argument. + * @returns {boolean} Returns `true` if the arguments are from an iteratee call, else `false`. + */ + function isIterateeCall(value, index, object) { + if (!isObject(object)) { + return false; + } + var type = typeof index; + if (type == 'number' + ? (isArrayLike(object) && isIndex(index, object.length)) + : (type == 'string' && index in object)) { + return eq(object[index], value); + } + return false; + } + + /** + * Checks if `value` is a property name and not a property path. + * + * @private + * @param {*} value The value to check. + * @param {Object} [object] The object to query keys on. + * @returns {boolean} Returns `true` if `value` is a property name, else `false`. + */ + function isKey(value, object) { + if (typeof value == 'number') { + return true; + } + return !isArray(value) && + (reIsPlainProp.test(value) || !reIsDeepProp.test(value) || + (object != null && value in Object(object))); + } + + /** + * Checks if `value` is suitable for use as unique object key. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is suitable, else `false`. + */ + function isKeyable(value) { + var type = typeof value; + return type == 'number' || type == 'boolean' || + (type == 'string' && value != '__proto__') || value == null; + } + + /** + * Checks if `func` has a lazy counterpart. + * + * @private + * @param {Function} func The function to check. + * @returns {boolean} Returns `true` if `func` has a lazy counterpart, else `false`. + */ + function isLaziable(func) { + var funcName = getFuncName(func), + other = lodash[funcName]; + + if (typeof other != 'function' || !(funcName in LazyWrapper.prototype)) { + return false; + } + if (func === other) { + return true; + } + var data = getData(other); + return !!data && func === data[0]; + } + + /** + * Checks if `value` is likely a prototype object. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a prototype, else `false`. + */ + function isPrototype(value) { + var Ctor = value && value.constructor, + proto = (isFunction(Ctor) && Ctor.prototype) || objectProto; + + return value === proto; + } + + /** + * Checks if `value` is suitable for strict equality comparisons, i.e. `===`. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` if suitable for strict + * equality comparisons, else `false`. + */ + function isStrictComparable(value) { + return value === value && !isObject(value); + } + + /** + * Merges the function metadata of `source` into `data`. + * + * Merging metadata reduces the number of wrappers used to invoke a function. + * This is possible because methods like `_.bind`, `_.curry`, and `_.partial` + * may be applied regardless of execution order. Methods like `_.ary` and `_.rearg` + * modify function arguments, making the order in which they are executed important, + * preventing the merging of metadata. However, we make an exception for a safe + * combined case where curried functions have `_.ary` and or `_.rearg` applied. + * + * @private + * @param {Array} data The destination metadata. + * @param {Array} source The source metadata. + * @returns {Array} Returns `data`. + */ + function mergeData(data, source) { + var bitmask = data[1], + srcBitmask = source[1], + newBitmask = bitmask | srcBitmask, + isCommon = newBitmask < (BIND_FLAG | BIND_KEY_FLAG | ARY_FLAG); + + var isCombo = + ((srcBitmask == ARY_FLAG) && (bitmask == CURRY_FLAG)) || + ((srcBitmask == ARY_FLAG) && (bitmask == REARG_FLAG) && (data[7].length <= source[8])) || + ((srcBitmask == (ARY_FLAG | REARG_FLAG)) && (source[7].length <= source[8]) && (bitmask == CURRY_FLAG)); + + // Exit early if metadata can't be merged. + if (!(isCommon || isCombo)) { + return data; + } + // Use source `thisArg` if available. + if (srcBitmask & BIND_FLAG) { + data[2] = source[2]; + // Set when currying a bound function. + newBitmask |= bitmask & BIND_FLAG ? 0 : CURRY_BOUND_FLAG; + } + // Compose partial arguments. + var value = source[3]; + if (value) { + var partials = data[3]; + data[3] = partials ? composeArgs(partials, value, source[4]) : copyArray(value); + data[4] = partials ? replaceHolders(data[3], PLACEHOLDER) : copyArray(source[4]); + } + // Compose partial right arguments. + value = source[5]; + if (value) { + partials = data[5]; + data[5] = partials ? composeArgsRight(partials, value, source[6]) : copyArray(value); + data[6] = partials ? replaceHolders(data[5], PLACEHOLDER) : copyArray(source[6]); + } + // Use source `argPos` if available. + value = source[7]; + if (value) { + data[7] = copyArray(value); + } + // Use source `ary` if it's smaller. + if (srcBitmask & ARY_FLAG) { + data[8] = data[8] == null ? source[8] : nativeMin(data[8], source[8]); + } + // Use source `arity` if one is not provided. + if (data[9] == null) { + data[9] = source[9]; + } + // Use source `func` and merge bitmasks. + data[0] = source[0]; + data[1] = newBitmask; + + return data; + } + + /** + * Used by `_.defaultsDeep` to customize its `_.merge` use. + * + * @private + * @param {*} objValue The destination value. + * @param {*} srcValue The source value. + * @param {string} key The key of the property to merge. + * @param {Object} object The parent object of `objValue`. + * @param {Object} source The parent object of `srcValue`. + * @param {Object} [stack] Tracks traversed source values and their merged counterparts. + * @returns {*} Returns the value to assign. + */ + function mergeDefaults(objValue, srcValue, key, object, source, stack) { + if (isObject(objValue) && isObject(srcValue)) { + stack.set(srcValue, objValue); + baseMerge(objValue, srcValue, undefined, mergeDefaults, stack); + } + return objValue; + } + + /** + * Gets the parent value at `path` of `object`. + * + * @private + * @param {Object} object The object to query. + * @param {Array} path The path to get the parent value of. + * @returns {*} Returns the parent value. + */ + function parent(object, path) { + return path.length == 1 ? object : get(object, baseSlice(path, 0, -1)); + } + + /** + * Reorder `array` according to the specified indexes where the element at + * the first index is assigned as the first element, the element at + * the second index is assigned as the second element, and so on. + * + * @private + * @param {Array} array The array to reorder. + * @param {Array} indexes The arranged array indexes. + * @returns {Array} Returns `array`. + */ + function reorder(array, indexes) { + var arrLength = array.length, + length = nativeMin(indexes.length, arrLength), + oldArray = copyArray(array); + + while (length--) { + var index = indexes[length]; + array[length] = isIndex(index, arrLength) ? oldArray[index] : undefined; + } + return array; + } + + /** + * Sets metadata for `func`. + * + * **Note:** If this function becomes hot, i.e. is invoked a lot in a short + * period of time, it will trip its breaker and transition to an identity function + * to avoid garbage collection pauses in V8. See [V8 issue 2070](https://code.google.com/p/v8/issues/detail?id=2070) + * for more details. + * + * @private + * @param {Function} func The function to associate metadata with. + * @param {*} data The metadata. + * @returns {Function} Returns `func`. + */ + var setData = (function() { + var count = 0, + lastCalled = 0; + + return function(key, value) { + var stamp = now(), + remaining = HOT_SPAN - (stamp - lastCalled); + + lastCalled = stamp; + if (remaining > 0) { + if (++count >= HOT_COUNT) { + return key; + } + } else { + count = 0; + } + return baseSetData(key, value); + }; + }()); + + /** + * Converts `string` to a property path array. + * + * @private + * @param {string} string The string to convert. + * @returns {Array} Returns the property path array. + */ + function stringToPath(string) { + var result = []; + toString(string).replace(rePropName, function(match, number, quote, string) { + result.push(quote ? string.replace(reEscapeChar, '$1') : (number || match)); + }); + return result; + } + + /** + * Creates a clone of `wrapper`. + * + * @private + * @param {Object} wrapper The wrapper to clone. + * @returns {Object} Returns the cloned wrapper. + */ + function wrapperClone(wrapper) { + if (wrapper instanceof LazyWrapper) { + return wrapper.clone(); + } + var result = new LodashWrapper(wrapper.__wrapped__, wrapper.__chain__); + result.__actions__ = copyArray(wrapper.__actions__); + result.__index__ = wrapper.__index__; + result.__values__ = wrapper.__values__; + return result; + } + + /*------------------------------------------------------------------------*/ + + /** + * Creates an array of elements split into groups the length of `size`. + * If `array` can't be split evenly, the final chunk will be the remaining + * elements. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to process. + * @param {number} [size=0] The length of each chunk. + * @returns {Array} Returns the new array containing chunks. + * @example + * + * _.chunk(['a', 'b', 'c', 'd'], 2); + * // => [['a', 'b'], ['c', 'd']] + * + * _.chunk(['a', 'b', 'c', 'd'], 3); + * // => [['a', 'b', 'c'], ['d']] + */ + function chunk(array, size) { + size = nativeMax(toInteger(size), 0); + + var length = array ? array.length : 0; + if (!length || size < 1) { + return []; + } + var index = 0, + resIndex = -1, + result = Array(nativeCeil(length / size)); + + while (index < length) { + result[++resIndex] = baseSlice(array, index, (index += size)); + } + return result; + } + + /** + * Creates an array with all falsey values removed. The values `false`, `null`, + * `0`, `""`, `undefined`, and `NaN` are falsey. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to compact. + * @returns {Array} Returns the new array of filtered values. + * @example + * + * _.compact([0, 1, false, 2, '', 3]); + * // => [1, 2, 3] + */ + function compact(array) { + var index = -1, + length = array ? array.length : 0, + resIndex = -1, + result = []; + + while (++index < length) { + var value = array[index]; + if (value) { + result[++resIndex] = value; + } + } + return result; + } + + /** + * Creates a new array concatenating `array` with any additional arrays + * and/or values. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to concatenate. + * @param {...*} [values] The values to concatenate. + * @returns {Array} Returns the new concatenated array. + * @example + * + * var array = [1]; + * var other = _.concat(array, 2, [3], [[4]]); + * + * console.log(other); + * // => [1, 2, 3, [4]] + * + * console.log(array); + * // => [1] + */ + var concat = rest(function(array, values) { + if (!isArray(array)) { + array = array == null ? [] : [Object(array)]; + } + values = baseFlatten(values, 1); + return arrayConcat(array, values); + }); + + /** + * Creates an array of unique `array` values not included in the other + * given arrays using [`SameValueZero`](http://ecma-international.org/ecma-262/6.0/#sec-samevaluezero) + * for equality comparisons. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to inspect. + * @param {...Array} [values] The values to exclude. + * @returns {Array} Returns the new array of filtered values. + * @example + * + * _.difference([3, 2, 1], [4, 2]); + * // => [3, 1] + */ + var difference = rest(function(array, values) { + return isArrayLikeObject(array) + ? baseDifference(array, baseFlatten(values, 1, true)) + : []; + }); + + /** + * This method is like `_.difference` except that it accepts `iteratee` which + * is invoked for each element of `array` and `values` to generate the criterion + * by which uniqueness is computed. The iteratee is invoked with one argument: (value). + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to inspect. + * @param {...Array} [values] The values to exclude. + * @param {Function|Object|string} [iteratee=_.identity] The iteratee invoked per element. + * @returns {Array} Returns the new array of filtered values. + * @example + * + * _.differenceBy([3.1, 2.2, 1.3], [4.4, 2.5], Math.floor); + * // => [3.1, 1.3] + * + * // The `_.property` iteratee shorthand. + * _.differenceBy([{ 'x': 2 }, { 'x': 1 }], [{ 'x': 1 }], 'x'); + * // => [{ 'x': 2 }] + */ + var differenceBy = rest(function(array, values) { + var iteratee = last(values); + if (isArrayLikeObject(iteratee)) { + iteratee = undefined; + } + return isArrayLikeObject(array) + ? baseDifference(array, baseFlatten(values, 1, true), getIteratee(iteratee)) + : []; + }); + + /** + * This method is like `_.difference` except that it accepts `comparator` + * which is invoked to compare elements of `array` to `values`. The comparator + * is invoked with two arguments: (arrVal, othVal). + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to inspect. + * @param {...Array} [values] The values to exclude. + * @param {Function} [comparator] The comparator invoked per element. + * @returns {Array} Returns the new array of filtered values. + * @example + * + * var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }]; + * + * _.differenceWith(objects, [{ 'x': 1, 'y': 2 }], _.isEqual); + * // => [{ 'x': 2, 'y': 1 }] + */ + var differenceWith = rest(function(array, values) { + var comparator = last(values); + if (isArrayLikeObject(comparator)) { + comparator = undefined; + } + return isArrayLikeObject(array) + ? baseDifference(array, baseFlatten(values, 1, true), undefined, comparator) + : []; + }); + + /** + * Creates a slice of `array` with `n` elements dropped from the beginning. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to query. + * @param {number} [n=1] The number of elements to drop. + * @param- {Object} [guard] Enables use as an iteratee for functions like `_.map`. + * @returns {Array} Returns the slice of `array`. + * @example + * + * _.drop([1, 2, 3]); + * // => [2, 3] + * + * _.drop([1, 2, 3], 2); + * // => [3] + * + * _.drop([1, 2, 3], 5); + * // => [] + * + * _.drop([1, 2, 3], 0); + * // => [1, 2, 3] + */ + function drop(array, n, guard) { + var length = array ? array.length : 0; + if (!length) { + return []; + } + n = (guard || n === undefined) ? 1 : toInteger(n); + return baseSlice(array, n < 0 ? 0 : n, length); + } + + /** + * Creates a slice of `array` with `n` elements dropped from the end. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to query. + * @param {number} [n=1] The number of elements to drop. + * @param- {Object} [guard] Enables use as an iteratee for functions like `_.map`. + * @returns {Array} Returns the slice of `array`. + * @example + * + * _.dropRight([1, 2, 3]); + * // => [1, 2] + * + * _.dropRight([1, 2, 3], 2); + * // => [1] + * + * _.dropRight([1, 2, 3], 5); + * // => [] + * + * _.dropRight([1, 2, 3], 0); + * // => [1, 2, 3] + */ + function dropRight(array, n, guard) { + var length = array ? array.length : 0; + if (!length) { + return []; + } + n = (guard || n === undefined) ? 1 : toInteger(n); + n = length - n; + return baseSlice(array, 0, n < 0 ? 0 : n); + } + + /** + * Creates a slice of `array` excluding elements dropped from the end. + * Elements are dropped until `predicate` returns falsey. The predicate is + * invoked with three arguments: (value, index, array). + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to query. + * @param {Function|Object|string} [predicate=_.identity] The function invoked per iteration. + * @returns {Array} Returns the slice of `array`. + * @example + * + * var users = [ + * { 'user': 'barney', 'active': true }, + * { 'user': 'fred', 'active': false }, + * { 'user': 'pebbles', 'active': false } + * ]; + * + * _.dropRightWhile(users, function(o) { return !o.active; }); + * // => objects for ['barney'] + * + * // The `_.matches` iteratee shorthand. + * _.dropRightWhile(users, { 'user': 'pebbles', 'active': false }); + * // => objects for ['barney', 'fred'] + * + * // The `_.matchesProperty` iteratee shorthand. + * _.dropRightWhile(users, ['active', false]); + * // => objects for ['barney'] + * + * // The `_.property` iteratee shorthand. + * _.dropRightWhile(users, 'active'); + * // => objects for ['barney', 'fred', 'pebbles'] + */ + function dropRightWhile(array, predicate) { + return (array && array.length) + ? baseWhile(array, getIteratee(predicate, 3), true, true) + : []; + } + + /** + * Creates a slice of `array` excluding elements dropped from the beginning. + * Elements are dropped until `predicate` returns falsey. The predicate is + * invoked with three arguments: (value, index, array). + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to query. + * @param {Function|Object|string} [predicate=_.identity] The function invoked per iteration. + * @returns {Array} Returns the slice of `array`. + * @example + * + * var users = [ + * { 'user': 'barney', 'active': false }, + * { 'user': 'fred', 'active': false }, + * { 'user': 'pebbles', 'active': true } + * ]; + * + * _.dropWhile(users, function(o) { return !o.active; }); + * // => objects for ['pebbles'] + * + * // The `_.matches` iteratee shorthand. + * _.dropWhile(users, { 'user': 'barney', 'active': false }); + * // => objects for ['fred', 'pebbles'] + * + * // The `_.matchesProperty` iteratee shorthand. + * _.dropWhile(users, ['active', false]); + * // => objects for ['pebbles'] + * + * // The `_.property` iteratee shorthand. + * _.dropWhile(users, 'active'); + * // => objects for ['barney', 'fred', 'pebbles'] + */ + function dropWhile(array, predicate) { + return (array && array.length) + ? baseWhile(array, getIteratee(predicate, 3), true) + : []; + } + + /** + * Fills elements of `array` with `value` from `start` up to, but not + * including, `end`. + * + * **Note:** This method mutates `array`. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to fill. + * @param {*} value The value to fill `array` with. + * @param {number} [start=0] The start position. + * @param {number} [end=array.length] The end position. + * @returns {Array} Returns `array`. + * @example + * + * var array = [1, 2, 3]; + * + * _.fill(array, 'a'); + * console.log(array); + * // => ['a', 'a', 'a'] + * + * _.fill(Array(3), 2); + * // => [2, 2, 2] + * + * _.fill([4, 6, 8, 10], '*', 1, 3); + * // => [4, '*', '*', 10] + */ + function fill(array, value, start, end) { + var length = array ? array.length : 0; + if (!length) { + return []; + } + if (start && typeof start != 'number' && isIterateeCall(array, value, start)) { + start = 0; + end = length; + } + return baseFill(array, value, start, end); + } + + /** + * This method is like `_.find` except that it returns the index of the first + * element `predicate` returns truthy for instead of the element itself. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to search. + * @param {Function|Object|string} [predicate=_.identity] The function invoked per iteration. + * @returns {number} Returns the index of the found element, else `-1`. + * @example + * + * var users = [ + * { 'user': 'barney', 'active': false }, + * { 'user': 'fred', 'active': false }, + * { 'user': 'pebbles', 'active': true } + * ]; + * + * _.findIndex(users, function(o) { return o.user == 'barney'; }); + * // => 0 + * + * // The `_.matches` iteratee shorthand. + * _.findIndex(users, { 'user': 'fred', 'active': false }); + * // => 1 + * + * // The `_.matchesProperty` iteratee shorthand. + * _.findIndex(users, ['active', false]); + * // => 0 + * + * // The `_.property` iteratee shorthand. + * _.findIndex(users, 'active'); + * // => 2 + */ + function findIndex(array, predicate) { + return (array && array.length) + ? baseFindIndex(array, getIteratee(predicate, 3)) + : -1; + } + + /** + * This method is like `_.findIndex` except that it iterates over elements + * of `collection` from right to left. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to search. + * @param {Function|Object|string} [predicate=_.identity] The function invoked per iteration. + * @returns {number} Returns the index of the found element, else `-1`. + * @example + * + * var users = [ + * { 'user': 'barney', 'active': true }, + * { 'user': 'fred', 'active': false }, + * { 'user': 'pebbles', 'active': false } + * ]; + * + * _.findLastIndex(users, function(o) { return o.user == 'pebbles'; }); + * // => 2 + * + * // The `_.matches` iteratee shorthand. + * _.findLastIndex(users, { 'user': 'barney', 'active': true }); + * // => 0 + * + * // The `_.matchesProperty` iteratee shorthand. + * _.findLastIndex(users, ['active', false]); + * // => 2 + * + * // The `_.property` iteratee shorthand. + * _.findLastIndex(users, 'active'); + * // => 0 + */ + function findLastIndex(array, predicate) { + return (array && array.length) + ? baseFindIndex(array, getIteratee(predicate, 3), true) + : -1; + } + + /** + * Flattens `array` a single level deep. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to flatten. + * @returns {Array} Returns the new flattened array. + * @example + * + * _.flatten([1, [2, [3, [4]], 5]]); + * // => [1, 2, [3, [4]], 5] + */ + function flatten(array) { + var length = array ? array.length : 0; + return length ? baseFlatten(array, 1) : []; + } + + /** + * Recursively flattens `array`. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to flatten. + * @returns {Array} Returns the new flattened array. + * @example + * + * _.flattenDeep([1, [2, [3, [4]], 5]]); + * // => [1, 2, 3, 4, 5] + */ + function flattenDeep(array) { + var length = array ? array.length : 0; + return length ? baseFlatten(array, INFINITY) : []; + } + + /** + * Recursively flatten `array` up to `depth` times. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to flatten. + * @param {number} [depth=1] The maximum recursion depth. + * @returns {Array} Returns the new flattened array. + * @example + * + * var array = [1, [2, [3, [4]], 5]]; + * + * _.flattenDepth(array, 1); + * // => [1, 2, [3, [4]], 5] + * + * _.flattenDepth(array, 2); + * // => [1, 2, 3, [4], 5] + */ + function flattenDepth(array, depth) { + var length = array ? array.length : 0; + if (!length) { + return []; + } + depth = depth === undefined ? 1 : toInteger(depth); + return baseFlatten(array, depth); + } + + /** + * The inverse of `_.toPairs`; this method returns an object composed + * from key-value `pairs`. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} pairs The key-value pairs. + * @returns {Object} Returns the new object. + * @example + * + * _.fromPairs([['fred', 30], ['barney', 40]]); + * // => { 'fred': 30, 'barney': 40 } + */ + function fromPairs(pairs) { + var index = -1, + length = pairs ? pairs.length : 0, + result = {}; + + while (++index < length) { + var pair = pairs[index]; + result[pair[0]] = pair[1]; + } + return result; + } + + /** + * Gets the first element of `array`. + * + * @static + * @memberOf _ + * @alias first + * @category Array + * @param {Array} array The array to query. + * @returns {*} Returns the first element of `array`. + * @example + * + * _.head([1, 2, 3]); + * // => 1 + * + * _.head([]); + * // => undefined + */ + function head(array) { + return array ? array[0] : undefined; + } + + /** + * Gets the index at which the first occurrence of `value` is found in `array` + * using [`SameValueZero`](http://ecma-international.org/ecma-262/6.0/#sec-samevaluezero) + * for equality comparisons. If `fromIndex` is negative, it's used as the offset + * from the end of `array`. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to search. + * @param {*} value The value to search for. + * @param {number} [fromIndex=0] The index to search from. + * @returns {number} Returns the index of the matched value, else `-1`. + * @example + * + * _.indexOf([1, 2, 1, 2], 2); + * // => 1 + * + * // Search from the `fromIndex`. + * _.indexOf([1, 2, 1, 2], 2, 2); + * // => 3 + */ + function indexOf(array, value, fromIndex) { + var length = array ? array.length : 0; + if (!length) { + return -1; + } + fromIndex = toInteger(fromIndex); + if (fromIndex < 0) { + fromIndex = nativeMax(length + fromIndex, 0); + } + return baseIndexOf(array, value, fromIndex); + } + + /** + * Gets all but the last element of `array`. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to query. + * @returns {Array} Returns the slice of `array`. + * @example + * + * _.initial([1, 2, 3]); + * // => [1, 2] + */ + function initial(array) { + return dropRight(array, 1); + } + + /** + * Creates an array of unique values that are included in all given arrays + * using [`SameValueZero`](http://ecma-international.org/ecma-262/6.0/#sec-samevaluezero) + * for equality comparisons. + * + * @static + * @memberOf _ + * @category Array + * @param {...Array} [arrays] The arrays to inspect. + * @returns {Array} Returns the new array of shared values. + * @example + * + * _.intersection([2, 1], [4, 2], [1, 2]); + * // => [2] + */ + var intersection = rest(function(arrays) { + var mapped = arrayMap(arrays, baseCastArrayLikeObject); + return (mapped.length && mapped[0] === arrays[0]) + ? baseIntersection(mapped) + : []; + }); + + /** + * This method is like `_.intersection` except that it accepts `iteratee` + * which is invoked for each element of each `arrays` to generate the criterion + * by which uniqueness is computed. The iteratee is invoked with one argument: (value). + * + * @static + * @memberOf _ + * @category Array + * @param {...Array} [arrays] The arrays to inspect. + * @param {Function|Object|string} [iteratee=_.identity] The iteratee invoked per element. + * @returns {Array} Returns the new array of shared values. + * @example + * + * _.intersectionBy([2.1, 1.2], [4.3, 2.4], Math.floor); + * // => [2.1] + * + * // The `_.property` iteratee shorthand. + * _.intersectionBy([{ 'x': 1 }], [{ 'x': 2 }, { 'x': 1 }], 'x'); + * // => [{ 'x': 1 }] + */ + var intersectionBy = rest(function(arrays) { + var iteratee = last(arrays), + mapped = arrayMap(arrays, baseCastArrayLikeObject); + + if (iteratee === last(mapped)) { + iteratee = undefined; + } else { + mapped.pop(); + } + return (mapped.length && mapped[0] === arrays[0]) + ? baseIntersection(mapped, getIteratee(iteratee)) + : []; + }); + + /** + * This method is like `_.intersection` except that it accepts `comparator` + * which is invoked to compare elements of `arrays`. The comparator is invoked + * with two arguments: (arrVal, othVal). + * + * @static + * @memberOf _ + * @category Array + * @param {...Array} [arrays] The arrays to inspect. + * @param {Function} [comparator] The comparator invoked per element. + * @returns {Array} Returns the new array of shared values. + * @example + * + * var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }]; + * var others = [{ 'x': 1, 'y': 1 }, { 'x': 1, 'y': 2 }]; + * + * _.intersectionWith(objects, others, _.isEqual); + * // => [{ 'x': 1, 'y': 2 }] + */ + var intersectionWith = rest(function(arrays) { + var comparator = last(arrays), + mapped = arrayMap(arrays, baseCastArrayLikeObject); + + if (comparator === last(mapped)) { + comparator = undefined; + } else { + mapped.pop(); + } + return (mapped.length && mapped[0] === arrays[0]) + ? baseIntersection(mapped, undefined, comparator) + : []; + }); + + /** + * Converts all elements in `array` into a string separated by `separator`. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to convert. + * @param {string} [separator=','] The element separator. + * @returns {string} Returns the joined string. + * @example + * + * _.join(['a', 'b', 'c'], '~'); + * // => 'a~b~c' + */ + function join(array, separator) { + return array ? nativeJoin.call(array, separator) : ''; + } + + /** + * Gets the last element of `array`. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to query. + * @returns {*} Returns the last element of `array`. + * @example + * + * _.last([1, 2, 3]); + * // => 3 + */ + function last(array) { + var length = array ? array.length : 0; + return length ? array[length - 1] : undefined; + } + + /** + * This method is like `_.indexOf` except that it iterates over elements of + * `array` from right to left. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to search. + * @param {*} value The value to search for. + * @param {number} [fromIndex=array.length-1] The index to search from. + * @returns {number} Returns the index of the matched value, else `-1`. + * @example + * + * _.lastIndexOf([1, 2, 1, 2], 2); + * // => 3 + * + * // Search from the `fromIndex`. + * _.lastIndexOf([1, 2, 1, 2], 2, 2); + * // => 1 + */ + function lastIndexOf(array, value, fromIndex) { + var length = array ? array.length : 0; + if (!length) { + return -1; + } + var index = length; + if (fromIndex !== undefined) { + index = toInteger(fromIndex); + index = (index < 0 ? nativeMax(length + index, 0) : nativeMin(index, length - 1)) + 1; + } + if (value !== value) { + return indexOfNaN(array, index, true); + } + while (index--) { + if (array[index] === value) { + return index; + } + } + return -1; + } + + /** + * Removes all given values from `array` using + * [`SameValueZero`](http://ecma-international.org/ecma-262/6.0/#sec-samevaluezero) + * for equality comparisons. + * + * **Note:** Unlike `_.without`, this method mutates `array`. Use `_.remove` + * to remove elements from an array by predicate. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to modify. + * @param {...*} [values] The values to remove. + * @returns {Array} Returns `array`. + * @example + * + * var array = [1, 2, 3, 1, 2, 3]; + * + * _.pull(array, 2, 3); + * console.log(array); + * // => [1, 1] + */ + var pull = rest(pullAll); + + /** + * This method is like `_.pull` except that it accepts an array of values to remove. + * + * **Note:** Unlike `_.difference`, this method mutates `array`. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to modify. + * @param {Array} values The values to remove. + * @returns {Array} Returns `array`. + * @example + * + * var array = [1, 2, 3, 1, 2, 3]; + * + * _.pullAll(array, [2, 3]); + * console.log(array); + * // => [1, 1] + */ + function pullAll(array, values) { + return (array && array.length && values && values.length) + ? basePullAll(array, values) + : array; + } + + /** + * This method is like `_.pullAll` except that it accepts `iteratee` which is + * invoked for each element of `array` and `values` to generate the criterion + * by which uniqueness is computed. The iteratee is invoked with one argument: (value). + * + * **Note:** Unlike `_.differenceBy`, this method mutates `array`. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to modify. + * @param {Array} values The values to remove. + * @param {Function|Object|string} [iteratee=_.identity] The iteratee invoked per element. + * @returns {Array} Returns `array`. + * @example + * + * var array = [{ 'x': 1 }, { 'x': 2 }, { 'x': 3 }, { 'x': 1 }]; + * + * _.pullAllBy(array, [{ 'x': 1 }, { 'x': 3 }], 'x'); + * console.log(array); + * // => [{ 'x': 2 }] + */ + function pullAllBy(array, values, iteratee) { + return (array && array.length && values && values.length) + ? basePullAllBy(array, values, getIteratee(iteratee)) + : array; + } + + /** + * Removes elements from `array` corresponding to `indexes` and returns an + * array of removed elements. + * + * **Note:** Unlike `_.at`, this method mutates `array`. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to modify. + * @param {...(number|number[])} [indexes] The indexes of elements to remove, + * specified individually or in arrays. + * @returns {Array} Returns the new array of removed elements. + * @example + * + * var array = [5, 10, 15, 20]; + * var evens = _.pullAt(array, 1, 3); + * + * console.log(array); + * // => [5, 15] + * + * console.log(evens); + * // => [10, 20] + */ + var pullAt = rest(function(array, indexes) { + indexes = arrayMap(baseFlatten(indexes, 1), String); + + var result = baseAt(array, indexes); + basePullAt(array, indexes.sort(compareAscending)); + return result; + }); + + /** + * Removes all elements from `array` that `predicate` returns truthy for + * and returns an array of the removed elements. The predicate is invoked + * with three arguments: (value, index, array). + * + * **Note:** Unlike `_.filter`, this method mutates `array`. Use `_.pull` + * to pull elements from an array by value. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to modify. + * @param {Function|Object|string} [predicate=_.identity] The function invoked per iteration. + * @returns {Array} Returns the new array of removed elements. + * @example + * + * var array = [1, 2, 3, 4]; + * var evens = _.remove(array, function(n) { + * return n % 2 == 0; + * }); + * + * console.log(array); + * // => [1, 3] + * + * console.log(evens); + * // => [2, 4] + */ + function remove(array, predicate) { + var result = []; + if (!(array && array.length)) { + return result; + } + var index = -1, + indexes = [], + length = array.length; + + predicate = getIteratee(predicate, 3); + while (++index < length) { + var value = array[index]; + if (predicate(value, index, array)) { + result.push(value); + indexes.push(index); + } + } + basePullAt(array, indexes); + return result; + } + + /** + * Reverses `array` so that the first element becomes the last, the second + * element becomes the second to last, and so on. + * + * **Note:** This method mutates `array` and is based on + * [`Array#reverse`](https://mdn.io/Array/reverse). + * + * @static + * @memberOf _ + * @category Array + * @returns {Array} Returns `array`. + * @example + * + * var array = [1, 2, 3]; + * + * _.reverse(array); + * // => [3, 2, 1] + * + * console.log(array); + * // => [3, 2, 1] + */ + function reverse(array) { + return array ? nativeReverse.call(array) : array; + } + + /** + * Creates a slice of `array` from `start` up to, but not including, `end`. + * + * **Note:** This method is used instead of [`Array#slice`](https://mdn.io/Array/slice) + * to ensure dense arrays are returned. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to slice. + * @param {number} [start=0] The start position. + * @param {number} [end=array.length] The end position. + * @returns {Array} Returns the slice of `array`. + */ + function slice(array, start, end) { + var length = array ? array.length : 0; + if (!length) { + return []; + } + if (end && typeof end != 'number' && isIterateeCall(array, start, end)) { + start = 0; + end = length; + } + else { + start = start == null ? 0 : toInteger(start); + end = end === undefined ? length : toInteger(end); + } + return baseSlice(array, start, end); + } + + /** + * Uses a binary search to determine the lowest index at which `value` should + * be inserted into `array` in order to maintain its sort order. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The sorted array to inspect. + * @param {*} value The value to evaluate. + * @returns {number} Returns the index at which `value` should be inserted into `array`. + * @example + * + * _.sortedIndex([30, 50], 40); + * // => 1 + * + * _.sortedIndex([4, 5], 4); + * // => 0 + */ + function sortedIndex(array, value) { + return baseSortedIndex(array, value); + } + + /** + * This method is like `_.sortedIndex` except that it accepts `iteratee` + * which is invoked for `value` and each element of `array` to compute their + * sort ranking. The iteratee is invoked with one argument: (value). + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The sorted array to inspect. + * @param {*} value The value to evaluate. + * @param {Function|Object|string} [iteratee=_.identity] The iteratee invoked per element. + * @returns {number} Returns the index at which `value` should be inserted into `array`. + * @example + * + * var dict = { 'thirty': 30, 'forty': 40, 'fifty': 50 }; + * + * _.sortedIndexBy(['thirty', 'fifty'], 'forty', _.propertyOf(dict)); + * // => 1 + * + * // The `_.property` iteratee shorthand. + * _.sortedIndexBy([{ 'x': 4 }, { 'x': 5 }], { 'x': 4 }, 'x'); + * // => 0 + */ + function sortedIndexBy(array, value, iteratee) { + return baseSortedIndexBy(array, value, getIteratee(iteratee)); + } + + /** + * This method is like `_.indexOf` except that it performs a binary + * search on a sorted `array`. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to search. + * @param {*} value The value to search for. + * @returns {number} Returns the index of the matched value, else `-1`. + * @example + * + * _.sortedIndexOf([1, 1, 2, 2], 2); + * // => 2 + */ + function sortedIndexOf(array, value) { + var length = array ? array.length : 0; + if (length) { + var index = baseSortedIndex(array, value); + if (index < length && eq(array[index], value)) { + return index; + } + } + return -1; + } + + /** + * This method is like `_.sortedIndex` except that it returns the highest + * index at which `value` should be inserted into `array` in order to + * maintain its sort order. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The sorted array to inspect. + * @param {*} value The value to evaluate. + * @returns {number} Returns the index at which `value` should be inserted into `array`. + * @example + * + * _.sortedLastIndex([4, 5], 4); + * // => 1 + */ + function sortedLastIndex(array, value) { + return baseSortedIndex(array, value, true); + } + + /** + * This method is like `_.sortedLastIndex` except that it accepts `iteratee` + * which is invoked for `value` and each element of `array` to compute their + * sort ranking. The iteratee is invoked with one argument: (value). + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The sorted array to inspect. + * @param {*} value The value to evaluate. + * @param {Function|Object|string} [iteratee=_.identity] The iteratee invoked per element. + * @returns {number} Returns the index at which `value` should be inserted into `array`. + * @example + * + * // The `_.property` iteratee shorthand. + * _.sortedLastIndexBy([{ 'x': 4 }, { 'x': 5 }], { 'x': 4 }, 'x'); + * // => 1 + */ + function sortedLastIndexBy(array, value, iteratee) { + return baseSortedIndexBy(array, value, getIteratee(iteratee), true); + } + + /** + * This method is like `_.lastIndexOf` except that it performs a binary + * search on a sorted `array`. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to search. + * @param {*} value The value to search for. + * @returns {number} Returns the index of the matched value, else `-1`. + * @example + * + * _.sortedLastIndexOf([1, 1, 2, 2], 2); + * // => 3 + */ + function sortedLastIndexOf(array, value) { + var length = array ? array.length : 0; + if (length) { + var index = baseSortedIndex(array, value, true) - 1; + if (eq(array[index], value)) { + return index; + } + } + return -1; + } + + /** + * This method is like `_.uniq` except that it's designed and optimized + * for sorted arrays. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to inspect. + * @returns {Array} Returns the new duplicate free array. + * @example + * + * _.sortedUniq([1, 1, 2]); + * // => [1, 2] + */ + function sortedUniq(array) { + return (array && array.length) + ? baseSortedUniq(array) + : []; + } + + /** + * This method is like `_.uniqBy` except that it's designed and optimized + * for sorted arrays. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to inspect. + * @param {Function} [iteratee] The iteratee invoked per element. + * @returns {Array} Returns the new duplicate free array. + * @example + * + * _.sortedUniqBy([1.1, 1.2, 2.3, 2.4], Math.floor); + * // => [1.1, 2.3] + */ + function sortedUniqBy(array, iteratee) { + return (array && array.length) + ? baseSortedUniqBy(array, getIteratee(iteratee)) + : []; + } + + /** + * Gets all but the first element of `array`. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to query. + * @returns {Array} Returns the slice of `array`. + * @example + * + * _.tail([1, 2, 3]); + * // => [2, 3] + */ + function tail(array) { + return drop(array, 1); + } + + /** + * Creates a slice of `array` with `n` elements taken from the beginning. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to query. + * @param {number} [n=1] The number of elements to take. + * @param- {Object} [guard] Enables use as an iteratee for functions like `_.map`. + * @returns {Array} Returns the slice of `array`. + * @example + * + * _.take([1, 2, 3]); + * // => [1] + * + * _.take([1, 2, 3], 2); + * // => [1, 2] + * + * _.take([1, 2, 3], 5); + * // => [1, 2, 3] + * + * _.take([1, 2, 3], 0); + * // => [] + */ + function take(array, n, guard) { + if (!(array && array.length)) { + return []; + } + n = (guard || n === undefined) ? 1 : toInteger(n); + return baseSlice(array, 0, n < 0 ? 0 : n); + } + + /** + * Creates a slice of `array` with `n` elements taken from the end. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to query. + * @param {number} [n=1] The number of elements to take. + * @param- {Object} [guard] Enables use as an iteratee for functions like `_.map`. + * @returns {Array} Returns the slice of `array`. + * @example + * + * _.takeRight([1, 2, 3]); + * // => [3] + * + * _.takeRight([1, 2, 3], 2); + * // => [2, 3] + * + * _.takeRight([1, 2, 3], 5); + * // => [1, 2, 3] + * + * _.takeRight([1, 2, 3], 0); + * // => [] + */ + function takeRight(array, n, guard) { + var length = array ? array.length : 0; + if (!length) { + return []; + } + n = (guard || n === undefined) ? 1 : toInteger(n); + n = length - n; + return baseSlice(array, n < 0 ? 0 : n, length); + } + + /** + * Creates a slice of `array` with elements taken from the end. Elements are + * taken until `predicate` returns falsey. The predicate is invoked with three + * arguments: (value, index, array). + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to query. + * @param {Function|Object|string} [predicate=_.identity] The function invoked per iteration. + * @returns {Array} Returns the slice of `array`. + * @example + * + * var users = [ + * { 'user': 'barney', 'active': true }, + * { 'user': 'fred', 'active': false }, + * { 'user': 'pebbles', 'active': false } + * ]; + * + * _.takeRightWhile(users, function(o) { return !o.active; }); + * // => objects for ['fred', 'pebbles'] + * + * // The `_.matches` iteratee shorthand. + * _.takeRightWhile(users, { 'user': 'pebbles', 'active': false }); + * // => objects for ['pebbles'] + * + * // The `_.matchesProperty` iteratee shorthand. + * _.takeRightWhile(users, ['active', false]); + * // => objects for ['fred', 'pebbles'] + * + * // The `_.property` iteratee shorthand. + * _.takeRightWhile(users, 'active'); + * // => [] + */ + function takeRightWhile(array, predicate) { + return (array && array.length) + ? baseWhile(array, getIteratee(predicate, 3), false, true) + : []; + } + + /** + * Creates a slice of `array` with elements taken from the beginning. Elements + * are taken until `predicate` returns falsey. The predicate is invoked with + * three arguments: (value, index, array). + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to query. + * @param {Function|Object|string} [predicate=_.identity] The function invoked per iteration. + * @returns {Array} Returns the slice of `array`. + * @example + * + * var users = [ + * { 'user': 'barney', 'active': false }, + * { 'user': 'fred', 'active': false}, + * { 'user': 'pebbles', 'active': true } + * ]; + * + * _.takeWhile(users, function(o) { return !o.active; }); + * // => objects for ['barney', 'fred'] + * + * // The `_.matches` iteratee shorthand. + * _.takeWhile(users, { 'user': 'barney', 'active': false }); + * // => objects for ['barney'] + * + * // The `_.matchesProperty` iteratee shorthand. + * _.takeWhile(users, ['active', false]); + * // => objects for ['barney', 'fred'] + * + * // The `_.property` iteratee shorthand. + * _.takeWhile(users, 'active'); + * // => [] + */ + function takeWhile(array, predicate) { + return (array && array.length) + ? baseWhile(array, getIteratee(predicate, 3)) + : []; + } + + /** + * Creates an array of unique values, in order, from all given arrays using + * [`SameValueZero`](http://ecma-international.org/ecma-262/6.0/#sec-samevaluezero) + * for equality comparisons. + * + * @static + * @memberOf _ + * @category Array + * @param {...Array} [arrays] The arrays to inspect. + * @returns {Array} Returns the new array of combined values. + * @example + * + * _.union([2, 1], [4, 2], [1, 2]); + * // => [2, 1, 4] + */ + var union = rest(function(arrays) { + return baseUniq(baseFlatten(arrays, 1, true)); + }); + + /** + * This method is like `_.union` except that it accepts `iteratee` which is + * invoked for each element of each `arrays` to generate the criterion by which + * uniqueness is computed. The iteratee is invoked with one argument: (value). + * + * @static + * @memberOf _ + * @category Array + * @param {...Array} [arrays] The arrays to inspect. + * @param {Function|Object|string} [iteratee=_.identity] The iteratee invoked per element. + * @returns {Array} Returns the new array of combined values. + * @example + * + * _.unionBy([2.1, 1.2], [4.3, 2.4], Math.floor); + * // => [2.1, 1.2, 4.3] + * + * // The `_.property` iteratee shorthand. + * _.unionBy([{ 'x': 1 }], [{ 'x': 2 }, { 'x': 1 }], 'x'); + * // => [{ 'x': 1 }, { 'x': 2 }] + */ + var unionBy = rest(function(arrays) { + var iteratee = last(arrays); + if (isArrayLikeObject(iteratee)) { + iteratee = undefined; + } + return baseUniq(baseFlatten(arrays, 1, true), getIteratee(iteratee)); + }); + + /** + * This method is like `_.union` except that it accepts `comparator` which + * is invoked to compare elements of `arrays`. The comparator is invoked + * with two arguments: (arrVal, othVal). + * + * @static + * @memberOf _ + * @category Array + * @param {...Array} [arrays] The arrays to inspect. + * @param {Function} [comparator] The comparator invoked per element. + * @returns {Array} Returns the new array of combined values. + * @example + * + * var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }]; + * var others = [{ 'x': 1, 'y': 1 }, { 'x': 1, 'y': 2 }]; + * + * _.unionWith(objects, others, _.isEqual); + * // => [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }, { 'x': 1, 'y': 1 }] + */ + var unionWith = rest(function(arrays) { + var comparator = last(arrays); + if (isArrayLikeObject(comparator)) { + comparator = undefined; + } + return baseUniq(baseFlatten(arrays, 1, true), undefined, comparator); + }); + + /** + * Creates a duplicate-free version of an array, using + * [`SameValueZero`](http://ecma-international.org/ecma-262/6.0/#sec-samevaluezero) + * for equality comparisons, in which only the first occurrence of each element + * is kept. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to inspect. + * @returns {Array} Returns the new duplicate free array. + * @example + * + * _.uniq([2, 1, 2]); + * // => [2, 1] + */ + function uniq(array) { + return (array && array.length) + ? baseUniq(array) + : []; + } + + /** + * This method is like `_.uniq` except that it accepts `iteratee` which is + * invoked for each element in `array` to generate the criterion by which + * uniqueness is computed. The iteratee is invoked with one argument: (value). + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to inspect. + * @param {Function|Object|string} [iteratee=_.identity] The iteratee invoked per element. + * @returns {Array} Returns the new duplicate free array. + * @example + * + * _.uniqBy([2.1, 1.2, 2.3], Math.floor); + * // => [2.1, 1.2] + * + * // The `_.property` iteratee shorthand. + * _.uniqBy([{ 'x': 1 }, { 'x': 2 }, { 'x': 1 }], 'x'); + * // => [{ 'x': 1 }, { 'x': 2 }] + */ + function uniqBy(array, iteratee) { + return (array && array.length) + ? baseUniq(array, getIteratee(iteratee)) + : []; + } + + /** + * This method is like `_.uniq` except that it accepts `comparator` which + * is invoked to compare elements of `array`. The comparator is invoked with + * two arguments: (arrVal, othVal). + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to inspect. + * @param {Function} [comparator] The comparator invoked per element. + * @returns {Array} Returns the new duplicate free array. + * @example + * + * var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }, { 'x': 1, 'y': 2 }]; + * + * _.uniqWith(objects, _.isEqual); + * // => [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }] + */ + function uniqWith(array, comparator) { + return (array && array.length) + ? baseUniq(array, undefined, comparator) + : []; + } + + /** + * This method is like `_.zip` except that it accepts an array of grouped + * elements and creates an array regrouping the elements to their pre-zip + * configuration. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array of grouped elements to process. + * @returns {Array} Returns the new array of regrouped elements. + * @example + * + * var zipped = _.zip(['fred', 'barney'], [30, 40], [true, false]); + * // => [['fred', 30, true], ['barney', 40, false]] + * + * _.unzip(zipped); + * // => [['fred', 'barney'], [30, 40], [true, false]] + */ + function unzip(array) { + if (!(array && array.length)) { + return []; + } + var length = 0; + array = arrayFilter(array, function(group) { + if (isArrayLikeObject(group)) { + length = nativeMax(group.length, length); + return true; + } + }); + return baseTimes(length, function(index) { + return arrayMap(array, baseProperty(index)); + }); + } + + /** + * This method is like `_.unzip` except that it accepts `iteratee` to specify + * how regrouped values should be combined. The iteratee is invoked with the + * elements of each group: (...group). + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array of grouped elements to process. + * @param {Function} [iteratee=_.identity] The function to combine regrouped values. + * @returns {Array} Returns the new array of regrouped elements. + * @example + * + * var zipped = _.zip([1, 2], [10, 20], [100, 200]); + * // => [[1, 10, 100], [2, 20, 200]] + * + * _.unzipWith(zipped, _.add); + * // => [3, 30, 300] + */ + function unzipWith(array, iteratee) { + if (!(array && array.length)) { + return []; + } + var result = unzip(array); + if (iteratee == null) { + return result; + } + return arrayMap(result, function(group) { + return apply(iteratee, undefined, group); + }); + } + + /** + * Creates an array excluding all given values using + * [`SameValueZero`](http://ecma-international.org/ecma-262/6.0/#sec-samevaluezero) + * for equality comparisons. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} array The array to filter. + * @param {...*} [values] The values to exclude. + * @returns {Array} Returns the new array of filtered values. + * @example + * + * _.without([1, 2, 1, 3], 1, 2); + * // => [3] + */ + var without = rest(function(array, values) { + return isArrayLikeObject(array) + ? baseDifference(array, values) + : []; + }); + + /** + * Creates an array of unique values that is the [symmetric difference](https://en.wikipedia.org/wiki/Symmetric_difference) + * of the given arrays. + * + * @static + * @memberOf _ + * @category Array + * @param {...Array} [arrays] The arrays to inspect. + * @returns {Array} Returns the new array of values. + * @example + * + * _.xor([2, 1], [4, 2]); + * // => [1, 4] + */ + var xor = rest(function(arrays) { + return baseXor(arrayFilter(arrays, isArrayLikeObject)); + }); + + /** + * This method is like `_.xor` except that it accepts `iteratee` which is + * invoked for each element of each `arrays` to generate the criterion by which + * uniqueness is computed. The iteratee is invoked with one argument: (value). + * + * @static + * @memberOf _ + * @category Array + * @param {...Array} [arrays] The arrays to inspect. + * @param {Function|Object|string} [iteratee=_.identity] The iteratee invoked per element. + * @returns {Array} Returns the new array of values. + * @example + * + * _.xorBy([2.1, 1.2], [4.3, 2.4], Math.floor); + * // => [1.2, 4.3] + * + * // The `_.property` iteratee shorthand. + * _.xorBy([{ 'x': 1 }], [{ 'x': 2 }, { 'x': 1 }], 'x'); + * // => [{ 'x': 2 }] + */ + var xorBy = rest(function(arrays) { + var iteratee = last(arrays); + if (isArrayLikeObject(iteratee)) { + iteratee = undefined; + } + return baseXor(arrayFilter(arrays, isArrayLikeObject), getIteratee(iteratee)); + }); + + /** + * This method is like `_.xor` except that it accepts `comparator` which is + * invoked to compare elements of `arrays`. The comparator is invoked with + * two arguments: (arrVal, othVal). + * + * @static + * @memberOf _ + * @category Array + * @param {...Array} [arrays] The arrays to inspect. + * @param {Function} [comparator] The comparator invoked per element. + * @returns {Array} Returns the new array of values. + * @example + * + * var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }]; + * var others = [{ 'x': 1, 'y': 1 }, { 'x': 1, 'y': 2 }]; + * + * _.xorWith(objects, others, _.isEqual); + * // => [{ 'x': 2, 'y': 1 }, { 'x': 1, 'y': 1 }] + */ + var xorWith = rest(function(arrays) { + var comparator = last(arrays); + if (isArrayLikeObject(comparator)) { + comparator = undefined; + } + return baseXor(arrayFilter(arrays, isArrayLikeObject), undefined, comparator); + }); + + /** + * Creates an array of grouped elements, the first of which contains the first + * elements of the given arrays, the second of which contains the second elements + * of the given arrays, and so on. + * + * @static + * @memberOf _ + * @category Array + * @param {...Array} [arrays] The arrays to process. + * @returns {Array} Returns the new array of grouped elements. + * @example + * + * _.zip(['fred', 'barney'], [30, 40], [true, false]); + * // => [['fred', 30, true], ['barney', 40, false]] + */ + var zip = rest(unzip); + + /** + * This method is like `_.fromPairs` except that it accepts two arrays, + * one of property names and one of corresponding values. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} [props=[]] The property names. + * @param {Array} [values=[]] The property values. + * @returns {Object} Returns the new object. + * @example + * + * _.zipObject(['a', 'b'], [1, 2]); + * // => { 'a': 1, 'b': 2 } + */ + function zipObject(props, values) { + return baseZipObject(props || [], values || [], assignValue); + } + + /** + * This method is like `_.zipObject` except that it supports property paths. + * + * @static + * @memberOf _ + * @category Array + * @param {Array} [props=[]] The property names. + * @param {Array} [values=[]] The property values. + * @returns {Object} Returns the new object. + * @example + * + * _.zipObjectDeep(['a.b[0].c', 'a.b[1].d'], [1, 2]); + * // => { 'a': { 'b': [{ 'c': 1 }, { 'd': 2 }] } } + */ + function zipObjectDeep(props, values) { + return baseZipObject(props || [], values || [], baseSet); + } + + /** + * This method is like `_.zip` except that it accepts `iteratee` to specify + * how grouped values should be combined. The iteratee is invoked with the + * elements of each group: (...group). + * + * @static + * @memberOf _ + * @category Array + * @param {...Array} [arrays] The arrays to process. + * @param {Function} [iteratee=_.identity] The function to combine grouped values. + * @returns {Array} Returns the new array of grouped elements. + * @example + * + * _.zipWith([1, 2], [10, 20], [100, 200], function(a, b, c) { + * return a + b + c; + * }); + * // => [111, 222] + */ + var zipWith = rest(function(arrays) { + var length = arrays.length, + iteratee = length > 1 ? arrays[length - 1] : undefined; + + iteratee = typeof iteratee == 'function' ? (arrays.pop(), iteratee) : undefined; + return unzipWith(arrays, iteratee); + }); + + /*------------------------------------------------------------------------*/ + + /** + * Creates a `lodash` object that wraps `value` with explicit method chaining enabled. + * The result of such method chaining must be unwrapped with `_#value`. + * + * @static + * @memberOf _ + * @category Seq + * @param {*} value The value to wrap. + * @returns {Object} Returns the new `lodash` wrapper instance. + * @example + * + * var users = [ + * { 'user': 'barney', 'age': 36 }, + * { 'user': 'fred', 'age': 40 }, + * { 'user': 'pebbles', 'age': 1 } + * ]; + * + * var youngest = _ + * .chain(users) + * .sortBy('age') + * .map(function(o) { + * return o.user + ' is ' + o.age; + * }) + * .head() + * .value(); + * // => 'pebbles is 1' + */ + function chain(value) { + var result = lodash(value); + result.__chain__ = true; + return result; + } + + /** + * This method invokes `interceptor` and returns `value`. The interceptor + * is invoked with one argument; (value). The purpose of this method is to + * "tap into" a method chain in order to modify intermediate results. + * + * @static + * @memberOf _ + * @category Seq + * @param {*} value The value to provide to `interceptor`. + * @param {Function} interceptor The function to invoke. + * @returns {*} Returns `value`. + * @example + * + * _([1, 2, 3]) + * .tap(function(array) { + * // Mutate input array. + * array.pop(); + * }) + * .reverse() + * .value(); + * // => [2, 1] + */ + function tap(value, interceptor) { + interceptor(value); + return value; + } + + /** + * This method is like `_.tap` except that it returns the result of `interceptor`. + * The purpose of this method is to "pass thru" values replacing intermediate + * results in a method chain. + * + * @static + * @memberOf _ + * @category Seq + * @param {*} value The value to provide to `interceptor`. + * @param {Function} interceptor The function to invoke. + * @returns {*} Returns the result of `interceptor`. + * @example + * + * _(' abc ') + * .chain() + * .trim() + * .thru(function(value) { + * return [value]; + * }) + * .value(); + * // => ['abc'] + */ + function thru(value, interceptor) { + return interceptor(value); + } + + /** + * This method is the wrapper version of `_.at`. + * + * @name at + * @memberOf _ + * @category Seq + * @param {...(string|string[])} [paths] The property paths of elements to pick, + * specified individually or in arrays. + * @returns {Object} Returns the new `lodash` wrapper instance. + * @example + * + * var object = { 'a': [{ 'b': { 'c': 3 } }, 4] }; + * + * _(object).at(['a[0].b.c', 'a[1]']).value(); + * // => [3, 4] + * + * _(['a', 'b', 'c']).at(0, 2).value(); + * // => ['a', 'c'] + */ + var wrapperAt = rest(function(paths) { + paths = baseFlatten(paths, 1); + var length = paths.length, + start = length ? paths[0] : 0, + value = this.__wrapped__, + interceptor = function(object) { return baseAt(object, paths); }; + + if (length > 1 || this.__actions__.length || + !(value instanceof LazyWrapper) || !isIndex(start)) { + return this.thru(interceptor); + } + value = value.slice(start, +start + (length ? 1 : 0)); + value.__actions__.push({ + 'func': thru, + 'args': [interceptor], + 'thisArg': undefined + }); + return new LodashWrapper(value, this.__chain__).thru(function(array) { + if (length && !array.length) { + array.push(undefined); + } + return array; + }); + }); + + /** + * Enables explicit method chaining on the wrapper object. + * + * @name chain + * @memberOf _ + * @category Seq + * @returns {Object} Returns the new `lodash` wrapper instance. + * @example + * + * var users = [ + * { 'user': 'barney', 'age': 36 }, + * { 'user': 'fred', 'age': 40 } + * ]; + * + * // A sequence without explicit chaining. + * _(users).head(); + * // => { 'user': 'barney', 'age': 36 } + * + * // A sequence with explicit chaining. + * _(users) + * .chain() + * .head() + * .pick('user') + * .value(); + * // => { 'user': 'barney' } + */ + function wrapperChain() { + return chain(this); + } + + /** + * Executes the chained sequence and returns the wrapped result. + * + * @name commit + * @memberOf _ + * @category Seq + * @returns {Object} Returns the new `lodash` wrapper instance. + * @example + * + * var array = [1, 2]; + * var wrapped = _(array).push(3); + * + * console.log(array); + * // => [1, 2] + * + * wrapped = wrapped.commit(); + * console.log(array); + * // => [1, 2, 3] + * + * wrapped.last(); + * // => 3 + * + * console.log(array); + * // => [1, 2, 3] + */ + function wrapperCommit() { + return new LodashWrapper(this.value(), this.__chain__); + } + + /** + * This method is the wrapper version of `_.flatMap`. + * + * @name flatMap + * @memberOf _ + * @category Seq + * @param {Function|Object|string} [iteratee=_.identity] The function invoked per iteration. + * @returns {Object} Returns the new `lodash` wrapper instance. + * @example + * + * function duplicate(n) { + * return [n, n]; + * } + * + * _([1, 2]).flatMap(duplicate).value(); + * // => [1, 1, 2, 2] + */ + function wrapperFlatMap(iteratee) { + return this.map(iteratee).flatten(); + } + + /** + * Gets the next value on a wrapped object following the + * [iterator protocol](https://mdn.io/iteration_protocols#iterator). + * + * @name next + * @memberOf _ + * @category Seq + * @returns {Object} Returns the next iterator value. + * @example + * + * var wrapped = _([1, 2]); + * + * wrapped.next(); + * // => { 'done': false, 'value': 1 } + * + * wrapped.next(); + * // => { 'done': false, 'value': 2 } + * + * wrapped.next(); + * // => { 'done': true, 'value': undefined } + */ + function wrapperNext() { + if (this.__values__ === undefined) { + this.__values__ = toArray(this.value()); + } + var done = this.__index__ >= this.__values__.length, + value = done ? undefined : this.__values__[this.__index__++]; + + return { 'done': done, 'value': value }; + } + + /** + * Enables the wrapper to be iterable. + * + * @name Symbol.iterator + * @memberOf _ + * @category Seq + * @returns {Object} Returns the wrapper object. + * @example + * + * var wrapped = _([1, 2]); + * + * wrapped[Symbol.iterator]() === wrapped; + * // => true + * + * Array.from(wrapped); + * // => [1, 2] + */ + function wrapperToIterator() { + return this; + } + + /** + * Creates a clone of the chained sequence planting `value` as the wrapped value. + * + * @name plant + * @memberOf _ + * @category Seq + * @param {*} value The value to plant. + * @returns {Object} Returns the new `lodash` wrapper instance. + * @example + * + * function square(n) { + * return n * n; + * } + * + * var wrapped = _([1, 2]).map(square); + * var other = wrapped.plant([3, 4]); + * + * other.value(); + * // => [9, 16] + * + * wrapped.value(); + * // => [1, 4] + */ + function wrapperPlant(value) { + var result, + parent = this; + + while (parent instanceof baseLodash) { + var clone = wrapperClone(parent); + clone.__index__ = 0; + clone.__values__ = undefined; + if (result) { + previous.__wrapped__ = clone; + } else { + result = clone; + } + var previous = clone; + parent = parent.__wrapped__; + } + previous.__wrapped__ = value; + return result; + } + + /** + * This method is the wrapper version of `_.reverse`. + * + * **Note:** This method mutates the wrapped array. + * + * @name reverse + * @memberOf _ + * @category Seq + * @returns {Object} Returns the new `lodash` wrapper instance. + * @example + * + * var array = [1, 2, 3]; + * + * _(array).reverse().value() + * // => [3, 2, 1] + * + * console.log(array); + * // => [3, 2, 1] + */ + function wrapperReverse() { + var value = this.__wrapped__; + if (value instanceof LazyWrapper) { + var wrapped = value; + if (this.__actions__.length) { + wrapped = new LazyWrapper(this); + } + wrapped = wrapped.reverse(); + wrapped.__actions__.push({ + 'func': thru, + 'args': [reverse], + 'thisArg': undefined + }); + return new LodashWrapper(wrapped, this.__chain__); + } + return this.thru(reverse); + } + + /** + * Executes the chained sequence to extract the unwrapped value. + * + * @name value + * @memberOf _ + * @alias toJSON, valueOf + * @category Seq + * @returns {*} Returns the resolved unwrapped value. + * @example + * + * _([1, 2, 3]).value(); + * // => [1, 2, 3] + */ + function wrapperValue() { + return baseWrapperValue(this.__wrapped__, this.__actions__); + } + + /*------------------------------------------------------------------------*/ + + /** + * Creates an object composed of keys generated from the results of running + * each element of `collection` through `iteratee`. The corresponding value + * of each key is the number of times the key was returned by `iteratee`. + * The iteratee is invoked with one argument: (value). + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function|Object|string} [iteratee=_.identity] The iteratee to transform keys. + * @returns {Object} Returns the composed aggregate object. + * @example + * + * _.countBy([6.1, 4.2, 6.3], Math.floor); + * // => { '4': 1, '6': 2 } + * + * _.countBy(['one', 'two', 'three'], 'length'); + * // => { '3': 2, '5': 1 } + */ + var countBy = createAggregator(function(result, value, key) { + hasOwnProperty.call(result, key) ? ++result[key] : (result[key] = 1); + }); + + /** + * Checks if `predicate` returns truthy for **all** elements of `collection`. + * Iteration is stopped once `predicate` returns falsey. The predicate is + * invoked with three arguments: (value, index|key, collection). + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function|Object|string} [predicate=_.identity] The function invoked per iteration. + * @param- {Object} [guard] Enables use as an iteratee for functions like `_.map`. + * @returns {boolean} Returns `true` if all elements pass the predicate check, else `false`. + * @example + * + * _.every([true, 1, null, 'yes'], Boolean); + * // => false + * + * var users = [ + * { 'user': 'barney', 'active': false }, + * { 'user': 'fred', 'active': false } + * ]; + * + * // The `_.matches` iteratee shorthand. + * _.every(users, { 'user': 'barney', 'active': false }); + * // => false + * + * // The `_.matchesProperty` iteratee shorthand. + * _.every(users, ['active', false]); + * // => true + * + * // The `_.property` iteratee shorthand. + * _.every(users, 'active'); + * // => false + */ + function every(collection, predicate, guard) { + var func = isArray(collection) ? arrayEvery : baseEvery; + if (guard && isIterateeCall(collection, predicate, guard)) { + predicate = undefined; + } + return func(collection, getIteratee(predicate, 3)); + } + + /** + * Iterates over elements of `collection`, returning an array of all elements + * `predicate` returns truthy for. The predicate is invoked with three arguments: + * (value, index|key, collection). + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function|Object|string} [predicate=_.identity] The function invoked per iteration. + * @returns {Array} Returns the new filtered array. + * @example + * + * var users = [ + * { 'user': 'barney', 'age': 36, 'active': true }, + * { 'user': 'fred', 'age': 40, 'active': false } + * ]; + * + * _.filter(users, function(o) { return !o.active; }); + * // => objects for ['fred'] + * + * // The `_.matches` iteratee shorthand. + * _.filter(users, { 'age': 36, 'active': true }); + * // => objects for ['barney'] + * + * // The `_.matchesProperty` iteratee shorthand. + * _.filter(users, ['active', false]); + * // => objects for ['fred'] + * + * // The `_.property` iteratee shorthand. + * _.filter(users, 'active'); + * // => objects for ['barney'] + */ + function filter(collection, predicate) { + var func = isArray(collection) ? arrayFilter : baseFilter; + return func(collection, getIteratee(predicate, 3)); + } + + /** + * Iterates over elements of `collection`, returning the first element + * `predicate` returns truthy for. The predicate is invoked with three arguments: + * (value, index|key, collection). + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object} collection The collection to search. + * @param {Function|Object|string} [predicate=_.identity] The function invoked per iteration. + * @returns {*} Returns the matched element, else `undefined`. + * @example + * + * var users = [ + * { 'user': 'barney', 'age': 36, 'active': true }, + * { 'user': 'fred', 'age': 40, 'active': false }, + * { 'user': 'pebbles', 'age': 1, 'active': true } + * ]; + * + * _.find(users, function(o) { return o.age < 40; }); + * // => object for 'barney' + * + * // The `_.matches` iteratee shorthand. + * _.find(users, { 'age': 1, 'active': true }); + * // => object for 'pebbles' + * + * // The `_.matchesProperty` iteratee shorthand. + * _.find(users, ['active', false]); + * // => object for 'fred' + * + * // The `_.property` iteratee shorthand. + * _.find(users, 'active'); + * // => object for 'barney' + */ + function find(collection, predicate) { + predicate = getIteratee(predicate, 3); + if (isArray(collection)) { + var index = baseFindIndex(collection, predicate); + return index > -1 ? collection[index] : undefined; + } + return baseFind(collection, predicate, baseEach); + } + + /** + * This method is like `_.find` except that it iterates over elements of + * `collection` from right to left. + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object} collection The collection to search. + * @param {Function|Object|string} [predicate=_.identity] The function invoked per iteration. + * @returns {*} Returns the matched element, else `undefined`. + * @example + * + * _.findLast([1, 2, 3, 4], function(n) { + * return n % 2 == 1; + * }); + * // => 3 + */ + function findLast(collection, predicate) { + predicate = getIteratee(predicate, 3); + if (isArray(collection)) { + var index = baseFindIndex(collection, predicate, true); + return index > -1 ? collection[index] : undefined; + } + return baseFind(collection, predicate, baseEachRight); + } + + /** + * Creates an array of flattened values by running each element in `collection` + * through `iteratee` and concating its result to the other mapped values. + * The iteratee is invoked with three arguments: (value, index|key, collection). + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function|Object|string} [iteratee=_.identity] The function invoked per iteration. + * @returns {Array} Returns the new flattened array. + * @example + * + * function duplicate(n) { + * return [n, n]; + * } + * + * _.flatMap([1, 2], duplicate); + * // => [1, 1, 2, 2] + */ + function flatMap(collection, iteratee) { + return baseFlatten(map(collection, iteratee), 1); + } + + /** + * Iterates over elements of `collection` invoking `iteratee` for each element. + * The iteratee is invoked with three arguments: (value, index|key, collection). + * Iteratee functions may exit iteration early by explicitly returning `false`. + * + * **Note:** As with other "Collections" methods, objects with a "length" property + * are iterated like arrays. To avoid this behavior use `_.forIn` or `_.forOwn` + * for object iteration. + * + * @static + * @memberOf _ + * @alias each + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @returns {Array|Object} Returns `collection`. + * @example + * + * _([1, 2]).forEach(function(value) { + * console.log(value); + * }); + * // => logs `1` then `2` + * + * _.forEach({ 'a': 1, 'b': 2 }, function(value, key) { + * console.log(key); + * }); + * // => logs 'a' then 'b' (iteration order is not guaranteed) + */ + function forEach(collection, iteratee) { + return (typeof iteratee == 'function' && isArray(collection)) + ? arrayEach(collection, iteratee) + : baseEach(collection, baseCastFunction(iteratee)); + } + + /** + * This method is like `_.forEach` except that it iterates over elements of + * `collection` from right to left. + * + * @static + * @memberOf _ + * @alias eachRight + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @returns {Array|Object} Returns `collection`. + * @example + * + * _.forEachRight([1, 2], function(value) { + * console.log(value); + * }); + * // => logs `2` then `1` + */ + function forEachRight(collection, iteratee) { + return (typeof iteratee == 'function' && isArray(collection)) + ? arrayEachRight(collection, iteratee) + : baseEachRight(collection, baseCastFunction(iteratee)); + } + + /** + * Creates an object composed of keys generated from the results of running + * each element of `collection` through `iteratee`. The corresponding value + * of each key is an array of elements responsible for generating the key. + * The iteratee is invoked with one argument: (value). + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function|Object|string} [iteratee=_.identity] The iteratee to transform keys. + * @returns {Object} Returns the composed aggregate object. + * @example + * + * _.groupBy([6.1, 4.2, 6.3], Math.floor); + * // => { '4': [4.2], '6': [6.1, 6.3] } + * + * // The `_.property` iteratee shorthand. + * _.groupBy(['one', 'two', 'three'], 'length'); + * // => { '3': ['one', 'two'], '5': ['three'] } + */ + var groupBy = createAggregator(function(result, value, key) { + if (hasOwnProperty.call(result, key)) { + result[key].push(value); + } else { + result[key] = [value]; + } + }); + + /** + * Checks if `value` is in `collection`. If `collection` is a string it's checked + * for a substring of `value`, otherwise [`SameValueZero`](http://ecma-international.org/ecma-262/6.0/#sec-samevaluezero) + * is used for equality comparisons. If `fromIndex` is negative, it's used as + * the offset from the end of `collection`. + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object|string} collection The collection to search. + * @param {*} value The value to search for. + * @param {number} [fromIndex=0] The index to search from. + * @param- {Object} [guard] Enables use as an iteratee for functions like `_.reduce`. + * @returns {boolean} Returns `true` if `value` is found, else `false`. + * @example + * + * _.includes([1, 2, 3], 1); + * // => true + * + * _.includes([1, 2, 3], 1, 2); + * // => false + * + * _.includes({ 'user': 'fred', 'age': 40 }, 'fred'); + * // => true + * + * _.includes('pebbles', 'eb'); + * // => true + */ + function includes(collection, value, fromIndex, guard) { + collection = isArrayLike(collection) ? collection : values(collection); + fromIndex = (fromIndex && !guard) ? toInteger(fromIndex) : 0; + + var length = collection.length; + if (fromIndex < 0) { + fromIndex = nativeMax(length + fromIndex, 0); + } + return isString(collection) + ? (fromIndex <= length && collection.indexOf(value, fromIndex) > -1) + : (!!length && baseIndexOf(collection, value, fromIndex) > -1); + } + + /** + * Invokes the method at `path` of each element in `collection`, returning + * an array of the results of each invoked method. Any additional arguments + * are provided to each invoked method. If `methodName` is a function it's + * invoked for, and `this` bound to, each element in `collection`. + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Array|Function|string} path The path of the method to invoke or + * the function invoked per iteration. + * @param {...*} [args] The arguments to invoke each method with. + * @returns {Array} Returns the array of results. + * @example + * + * _.invokeMap([[5, 1, 7], [3, 2, 1]], 'sort'); + * // => [[1, 5, 7], [1, 2, 3]] + * + * _.invokeMap([123, 456], String.prototype.split, ''); + * // => [['1', '2', '3'], ['4', '5', '6']] + */ + var invokeMap = rest(function(collection, path, args) { + var index = -1, + isFunc = typeof path == 'function', + isProp = isKey(path), + result = isArrayLike(collection) ? Array(collection.length) : []; + + baseEach(collection, function(value) { + var func = isFunc ? path : ((isProp && value != null) ? value[path] : undefined); + result[++index] = func ? apply(func, value, args) : baseInvoke(value, path, args); + }); + return result; + }); + + /** + * Creates an object composed of keys generated from the results of running + * each element of `collection` through `iteratee`. The corresponding value + * of each key is the last element responsible for generating the key. The + * iteratee is invoked with one argument: (value). + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function|Object|string} [iteratee=_.identity] The iteratee to transform keys. + * @returns {Object} Returns the composed aggregate object. + * @example + * + * var array = [ + * { 'dir': 'left', 'code': 97 }, + * { 'dir': 'right', 'code': 100 } + * ]; + * + * _.keyBy(array, function(o) { + * return String.fromCharCode(o.code); + * }); + * // => { 'a': { 'dir': 'left', 'code': 97 }, 'd': { 'dir': 'right', 'code': 100 } } + * + * _.keyBy(array, 'dir'); + * // => { 'left': { 'dir': 'left', 'code': 97 }, 'right': { 'dir': 'right', 'code': 100 } } + */ + var keyBy = createAggregator(function(result, value, key) { + result[key] = value; + }); + + /** + * Creates an array of values by running each element in `collection` through + * `iteratee`. The iteratee is invoked with three arguments: + * (value, index|key, collection). + * + * Many lodash methods are guarded to work as iteratees for methods like + * `_.every`, `_.filter`, `_.map`, `_.mapValues`, `_.reject`, and `_.some`. + * + * The guarded methods are: + * `ary`, `curry`, `curryRight`, `drop`, `dropRight`, `every`, `fill`, + * `invert`, `parseInt`, `random`, `range`, `rangeRight`, `slice`, `some`, + * `sortBy`, `take`, `takeRight`, `template`, `trim`, `trimEnd`, `trimStart`, + * and `words` + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function|Object|string} [iteratee=_.identity] The function invoked per iteration. + * @returns {Array} Returns the new mapped array. + * @example + * + * function square(n) { + * return n * n; + * } + * + * _.map([4, 8], square); + * // => [16, 64] + * + * _.map({ 'a': 4, 'b': 8 }, square); + * // => [16, 64] (iteration order is not guaranteed) + * + * var users = [ + * { 'user': 'barney' }, + * { 'user': 'fred' } + * ]; + * + * // The `_.property` iteratee shorthand. + * _.map(users, 'user'); + * // => ['barney', 'fred'] + */ + function map(collection, iteratee) { + var func = isArray(collection) ? arrayMap : baseMap; + return func(collection, getIteratee(iteratee, 3)); + } + + /** + * This method is like `_.sortBy` except that it allows specifying the sort + * orders of the iteratees to sort by. If `orders` is unspecified, all values + * are sorted in ascending order. Otherwise, specify an order of "desc" for + * descending or "asc" for ascending sort order of corresponding values. + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function[]|Object[]|string[]} [iteratees=[_.identity]] The iteratees to sort by. + * @param {string[]} [orders] The sort orders of `iteratees`. + * @param- {Object} [guard] Enables use as an iteratee for functions like `_.reduce`. + * @returns {Array} Returns the new sorted array. + * @example + * + * var users = [ + * { 'user': 'fred', 'age': 48 }, + * { 'user': 'barney', 'age': 34 }, + * { 'user': 'fred', 'age': 42 }, + * { 'user': 'barney', 'age': 36 } + * ]; + * + * // Sort by `user` in ascending order and by `age` in descending order. + * _.orderBy(users, ['user', 'age'], ['asc', 'desc']); + * // => objects for [['barney', 36], ['barney', 34], ['fred', 48], ['fred', 42]] + */ + function orderBy(collection, iteratees, orders, guard) { + if (collection == null) { + return []; + } + if (!isArray(iteratees)) { + iteratees = iteratees == null ? [] : [iteratees]; + } + orders = guard ? undefined : orders; + if (!isArray(orders)) { + orders = orders == null ? [] : [orders]; + } + return baseOrderBy(collection, iteratees, orders); + } + + /** + * Creates an array of elements split into two groups, the first of which + * contains elements `predicate` returns truthy for, the second of which + * contains elements `predicate` returns falsey for. The predicate is + * invoked with one argument: (value). + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function|Object|string} [predicate=_.identity] The function invoked per iteration. + * @returns {Array} Returns the array of grouped elements. + * @example + * + * var users = [ + * { 'user': 'barney', 'age': 36, 'active': false }, + * { 'user': 'fred', 'age': 40, 'active': true }, + * { 'user': 'pebbles', 'age': 1, 'active': false } + * ]; + * + * _.partition(users, function(o) { return o.active; }); + * // => objects for [['fred'], ['barney', 'pebbles']] + * + * // The `_.matches` iteratee shorthand. + * _.partition(users, { 'age': 1, 'active': false }); + * // => objects for [['pebbles'], ['barney', 'fred']] + * + * // The `_.matchesProperty` iteratee shorthand. + * _.partition(users, ['active', false]); + * // => objects for [['barney', 'pebbles'], ['fred']] + * + * // The `_.property` iteratee shorthand. + * _.partition(users, 'active'); + * // => objects for [['fred'], ['barney', 'pebbles']] + */ + var partition = createAggregator(function(result, value, key) { + result[key ? 0 : 1].push(value); + }, function() { return [[], []]; }); + + /** + * Reduces `collection` to a value which is the accumulated result of running + * each element in `collection` through `iteratee`, where each successive + * invocation is supplied the return value of the previous. If `accumulator` + * is not given the first element of `collection` is used as the initial + * value. The iteratee is invoked with four arguments: + * (accumulator, value, index|key, collection). + * + * Many lodash methods are guarded to work as iteratees for methods like + * `_.reduce`, `_.reduceRight`, and `_.transform`. + * + * The guarded methods are: + * `assign`, `defaults`, `defaultsDeep`, `includes`, `merge`, `orderBy`, + * and `sortBy` + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @param {*} [accumulator] The initial value. + * @returns {*} Returns the accumulated value. + * @example + * + * _.reduce([1, 2], function(sum, n) { + * return sum + n; + * }, 0); + * // => 3 + * + * _.reduce({ 'a': 1, 'b': 2, 'c': 1 }, function(result, value, key) { + * (result[value] || (result[value] = [])).push(key); + * return result; + * }, {}); + * // => { '1': ['a', 'c'], '2': ['b'] } (iteration order is not guaranteed) + */ + function reduce(collection, iteratee, accumulator) { + var func = isArray(collection) ? arrayReduce : baseReduce, + initAccum = arguments.length < 3; + + return func(collection, getIteratee(iteratee, 4), accumulator, initAccum, baseEach); + } + + /** + * This method is like `_.reduce` except that it iterates over elements of + * `collection` from right to left. + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @param {*} [accumulator] The initial value. + * @returns {*} Returns the accumulated value. + * @example + * + * var array = [[0, 1], [2, 3], [4, 5]]; + * + * _.reduceRight(array, function(flattened, other) { + * return flattened.concat(other); + * }, []); + * // => [4, 5, 2, 3, 0, 1] + */ + function reduceRight(collection, iteratee, accumulator) { + var func = isArray(collection) ? arrayReduceRight : baseReduce, + initAccum = arguments.length < 3; + + return func(collection, getIteratee(iteratee, 4), accumulator, initAccum, baseEachRight); + } + + /** + * The opposite of `_.filter`; this method returns the elements of `collection` + * that `predicate` does **not** return truthy for. + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function|Object|string} [predicate=_.identity] The function invoked per iteration. + * @returns {Array} Returns the new filtered array. + * @example + * + * var users = [ + * { 'user': 'barney', 'age': 36, 'active': false }, + * { 'user': 'fred', 'age': 40, 'active': true } + * ]; + * + * _.reject(users, function(o) { return !o.active; }); + * // => objects for ['fred'] + * + * // The `_.matches` iteratee shorthand. + * _.reject(users, { 'age': 40, 'active': true }); + * // => objects for ['barney'] + * + * // The `_.matchesProperty` iteratee shorthand. + * _.reject(users, ['active', false]); + * // => objects for ['fred'] + * + * // The `_.property` iteratee shorthand. + * _.reject(users, 'active'); + * // => objects for ['barney'] + */ + function reject(collection, predicate) { + var func = isArray(collection) ? arrayFilter : baseFilter; + predicate = getIteratee(predicate, 3); + return func(collection, function(value, index, collection) { + return !predicate(value, index, collection); + }); + } + + /** + * Gets a random element from `collection`. + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object} collection The collection to sample. + * @returns {*} Returns the random element. + * @example + * + * _.sample([1, 2, 3, 4]); + * // => 2 + */ + function sample(collection) { + var array = isArrayLike(collection) ? collection : values(collection), + length = array.length; + + return length > 0 ? array[baseRandom(0, length - 1)] : undefined; + } + + /** + * Gets `n` random elements at unique keys from `collection` up to the + * size of `collection`. + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object} collection The collection to sample. + * @param {number} [n=0] The number of elements to sample. + * @returns {Array} Returns the random elements. + * @example + * + * _.sampleSize([1, 2, 3], 2); + * // => [3, 1] + * + * _.sampleSize([1, 2, 3], 4); + * // => [2, 3, 1] + */ + function sampleSize(collection, n) { + var index = -1, + result = toArray(collection), + length = result.length, + lastIndex = length - 1; + + n = baseClamp(toInteger(n), 0, length); + while (++index < n) { + var rand = baseRandom(index, lastIndex), + value = result[rand]; + + result[rand] = result[index]; + result[index] = value; + } + result.length = n; + return result; + } + + /** + * Creates an array of shuffled values, using a version of the + * [Fisher-Yates shuffle](https://en.wikipedia.org/wiki/Fisher-Yates_shuffle). + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object} collection The collection to shuffle. + * @returns {Array} Returns the new shuffled array. + * @example + * + * _.shuffle([1, 2, 3, 4]); + * // => [4, 1, 3, 2] + */ + function shuffle(collection) { + return sampleSize(collection, MAX_ARRAY_LENGTH); + } + + /** + * Gets the size of `collection` by returning its length for array-like + * values or the number of own enumerable properties for objects. + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object} collection The collection to inspect. + * @returns {number} Returns the collection size. + * @example + * + * _.size([1, 2, 3]); + * // => 3 + * + * _.size({ 'a': 1, 'b': 2 }); + * // => 2 + * + * _.size('pebbles'); + * // => 7 + */ + function size(collection) { + if (collection == null) { + return 0; + } + if (isArrayLike(collection)) { + var result = collection.length; + return (result && isString(collection)) ? stringSize(collection) : result; + } + return keys(collection).length; + } + + /** + * Checks if `predicate` returns truthy for **any** element of `collection`. + * Iteration is stopped once `predicate` returns truthy. The predicate is + * invoked with three arguments: (value, index|key, collection). + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function|Object|string} [predicate=_.identity] The function invoked per iteration. + * @param- {Object} [guard] Enables use as an iteratee for functions like `_.map`. + * @returns {boolean} Returns `true` if any element passes the predicate check, else `false`. + * @example + * + * _.some([null, 0, 'yes', false], Boolean); + * // => true + * + * var users = [ + * { 'user': 'barney', 'active': true }, + * { 'user': 'fred', 'active': false } + * ]; + * + * // The `_.matches` iteratee shorthand. + * _.some(users, { 'user': 'barney', 'active': false }); + * // => false + * + * // The `_.matchesProperty` iteratee shorthand. + * _.some(users, ['active', false]); + * // => true + * + * // The `_.property` iteratee shorthand. + * _.some(users, 'active'); + * // => true + */ + function some(collection, predicate, guard) { + var func = isArray(collection) ? arraySome : baseSome; + if (guard && isIterateeCall(collection, predicate, guard)) { + predicate = undefined; + } + return func(collection, getIteratee(predicate, 3)); + } + + /** + * Creates an array of elements, sorted in ascending order by the results of + * running each element in a collection through each iteratee. This method + * performs a stable sort, that is, it preserves the original sort order of + * equal elements. The iteratees are invoked with one argument: (value). + * + * @static + * @memberOf _ + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {...(Function|Function[]|Object|Object[]|string|string[])} [iteratees=[_.identity]] + * The iteratees to sort by, specified individually or in arrays. + * @returns {Array} Returns the new sorted array. + * @example + * + * var users = [ + * { 'user': 'fred', 'age': 48 }, + * { 'user': 'barney', 'age': 36 }, + * { 'user': 'fred', 'age': 42 }, + * { 'user': 'barney', 'age': 34 } + * ]; + * + * _.sortBy(users, function(o) { return o.user; }); + * // => objects for [['barney', 36], ['barney', 34], ['fred', 48], ['fred', 42]] + * + * _.sortBy(users, ['user', 'age']); + * // => objects for [['barney', 34], ['barney', 36], ['fred', 42], ['fred', 48]] + * + * _.sortBy(users, 'user', function(o) { + * return Math.floor(o.age / 10); + * }); + * // => objects for [['barney', 36], ['barney', 34], ['fred', 48], ['fred', 42]] + */ + var sortBy = rest(function(collection, iteratees) { + if (collection == null) { + return []; + } + var length = iteratees.length; + if (length > 1 && isIterateeCall(collection, iteratees[0], iteratees[1])) { + iteratees = []; + } else if (length > 2 && isIterateeCall(iteratees[0], iteratees[1], iteratees[2])) { + iteratees.length = 1; + } + return baseOrderBy(collection, baseFlatten(iteratees, 1), []); + }); + + /*------------------------------------------------------------------------*/ + + /** + * Gets the timestamp of the number of milliseconds that have elapsed since + * the Unix epoch (1 January 1970 00:00:00 UTC). + * + * @static + * @memberOf _ + * @type {Function} + * @category Date + * @returns {number} Returns the timestamp. + * @example + * + * _.defer(function(stamp) { + * console.log(_.now() - stamp); + * }, _.now()); + * // => logs the number of milliseconds it took for the deferred function to be invoked + */ + var now = Date.now; + + /*------------------------------------------------------------------------*/ + + /** + * The opposite of `_.before`; this method creates a function that invokes + * `func` once it's called `n` or more times. + * + * @static + * @memberOf _ + * @category Function + * @param {number} n The number of calls before `func` is invoked. + * @param {Function} func The function to restrict. + * @returns {Function} Returns the new restricted function. + * @example + * + * var saves = ['profile', 'settings']; + * + * var done = _.after(saves.length, function() { + * console.log('done saving!'); + * }); + * + * _.forEach(saves, function(type) { + * asyncSave({ 'type': type, 'complete': done }); + * }); + * // => logs 'done saving!' after the two async saves have completed + */ + function after(n, func) { + if (typeof func != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + n = toInteger(n); + return function() { + if (--n < 1) { + return func.apply(this, arguments); + } + }; + } + + /** + * Creates a function that accepts up to `n` arguments, ignoring any + * additional arguments. + * + * @static + * @memberOf _ + * @category Function + * @param {Function} func The function to cap arguments for. + * @param {number} [n=func.length] The arity cap. + * @param- {Object} [guard] Enables use as an iteratee for functions like `_.map`. + * @returns {Function} Returns the new function. + * @example + * + * _.map(['6', '8', '10'], _.ary(parseInt, 1)); + * // => [6, 8, 10] + */ + function ary(func, n, guard) { + n = guard ? undefined : n; + n = (func && n == null) ? func.length : n; + return createWrapper(func, ARY_FLAG, undefined, undefined, undefined, undefined, n); + } + + /** + * Creates a function that invokes `func`, with the `this` binding and arguments + * of the created function, while it's called less than `n` times. Subsequent + * calls to the created function return the result of the last `func` invocation. + * + * @static + * @memberOf _ + * @category Function + * @param {number} n The number of calls at which `func` is no longer invoked. + * @param {Function} func The function to restrict. + * @returns {Function} Returns the new restricted function. + * @example + * + * jQuery(element).on('click', _.before(5, addContactToList)); + * // => allows adding up to 4 contacts to the list + */ + function before(n, func) { + var result; + if (typeof func != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + n = toInteger(n); + return function() { + if (--n > 0) { + result = func.apply(this, arguments); + } + if (n <= 1) { + func = undefined; + } + return result; + }; + } + + /** + * Creates a function that invokes `func` with the `this` binding of `thisArg` + * and prepends any additional `_.bind` arguments to those provided to the + * bound function. + * + * The `_.bind.placeholder` value, which defaults to `_` in monolithic builds, + * may be used as a placeholder for partially applied arguments. + * + * **Note:** Unlike native `Function#bind` this method doesn't set the "length" + * property of bound functions. + * + * @static + * @memberOf _ + * @category Function + * @param {Function} func The function to bind. + * @param {*} thisArg The `this` binding of `func`. + * @param {...*} [partials] The arguments to be partially applied. + * @returns {Function} Returns the new bound function. + * @example + * + * var greet = function(greeting, punctuation) { + * return greeting + ' ' + this.user + punctuation; + * }; + * + * var object = { 'user': 'fred' }; + * + * var bound = _.bind(greet, object, 'hi'); + * bound('!'); + * // => 'hi fred!' + * + * // Bound with placeholders. + * var bound = _.bind(greet, object, _, '!'); + * bound('hi'); + * // => 'hi fred!' + */ + var bind = rest(function(func, thisArg, partials) { + var bitmask = BIND_FLAG; + if (partials.length) { + var holders = replaceHolders(partials, getPlaceholder(bind)); + bitmask |= PARTIAL_FLAG; + } + return createWrapper(func, bitmask, thisArg, partials, holders); + }); + + /** + * Creates a function that invokes the method at `object[key]` and prepends + * any additional `_.bindKey` arguments to those provided to the bound function. + * + * This method differs from `_.bind` by allowing bound functions to reference + * methods that may be redefined or don't yet exist. + * See [Peter Michaux's article](http://peter.michaux.ca/articles/lazy-function-definition-pattern) + * for more details. + * + * The `_.bindKey.placeholder` value, which defaults to `_` in monolithic + * builds, may be used as a placeholder for partially applied arguments. + * + * @static + * @memberOf _ + * @category Function + * @param {Object} object The object to invoke the method on. + * @param {string} key The key of the method. + * @param {...*} [partials] The arguments to be partially applied. + * @returns {Function} Returns the new bound function. + * @example + * + * var object = { + * 'user': 'fred', + * 'greet': function(greeting, punctuation) { + * return greeting + ' ' + this.user + punctuation; + * } + * }; + * + * var bound = _.bindKey(object, 'greet', 'hi'); + * bound('!'); + * // => 'hi fred!' + * + * object.greet = function(greeting, punctuation) { + * return greeting + 'ya ' + this.user + punctuation; + * }; + * + * bound('!'); + * // => 'hiya fred!' + * + * // Bound with placeholders. + * var bound = _.bindKey(object, 'greet', _, '!'); + * bound('hi'); + * // => 'hiya fred!' + */ + var bindKey = rest(function(object, key, partials) { + var bitmask = BIND_FLAG | BIND_KEY_FLAG; + if (partials.length) { + var holders = replaceHolders(partials, getPlaceholder(bindKey)); + bitmask |= PARTIAL_FLAG; + } + return createWrapper(key, bitmask, object, partials, holders); + }); + + /** + * Creates a function that accepts arguments of `func` and either invokes + * `func` returning its result, if at least `arity` number of arguments have + * been provided, or returns a function that accepts the remaining `func` + * arguments, and so on. The arity of `func` may be specified if `func.length` + * is not sufficient. + * + * The `_.curry.placeholder` value, which defaults to `_` in monolithic builds, + * may be used as a placeholder for provided arguments. + * + * **Note:** This method doesn't set the "length" property of curried functions. + * + * @static + * @memberOf _ + * @category Function + * @param {Function} func The function to curry. + * @param {number} [arity=func.length] The arity of `func`. + * @param- {Object} [guard] Enables use as an iteratee for functions like `_.map`. + * @returns {Function} Returns the new curried function. + * @example + * + * var abc = function(a, b, c) { + * return [a, b, c]; + * }; + * + * var curried = _.curry(abc); + * + * curried(1)(2)(3); + * // => [1, 2, 3] + * + * curried(1, 2)(3); + * // => [1, 2, 3] + * + * curried(1, 2, 3); + * // => [1, 2, 3] + * + * // Curried with placeholders. + * curried(1)(_, 3)(2); + * // => [1, 2, 3] + */ + function curry(func, arity, guard) { + arity = guard ? undefined : arity; + var result = createWrapper(func, CURRY_FLAG, undefined, undefined, undefined, undefined, undefined, arity); + result.placeholder = curry.placeholder; + return result; + } + + /** + * This method is like `_.curry` except that arguments are applied to `func` + * in the manner of `_.partialRight` instead of `_.partial`. + * + * The `_.curryRight.placeholder` value, which defaults to `_` in monolithic + * builds, may be used as a placeholder for provided arguments. + * + * **Note:** This method doesn't set the "length" property of curried functions. + * + * @static + * @memberOf _ + * @category Function + * @param {Function} func The function to curry. + * @param {number} [arity=func.length] The arity of `func`. + * @param- {Object} [guard] Enables use as an iteratee for functions like `_.map`. + * @returns {Function} Returns the new curried function. + * @example + * + * var abc = function(a, b, c) { + * return [a, b, c]; + * }; + * + * var curried = _.curryRight(abc); + * + * curried(3)(2)(1); + * // => [1, 2, 3] + * + * curried(2, 3)(1); + * // => [1, 2, 3] + * + * curried(1, 2, 3); + * // => [1, 2, 3] + * + * // Curried with placeholders. + * curried(3)(1, _)(2); + * // => [1, 2, 3] + */ + function curryRight(func, arity, guard) { + arity = guard ? undefined : arity; + var result = createWrapper(func, CURRY_RIGHT_FLAG, undefined, undefined, undefined, undefined, undefined, arity); + result.placeholder = curryRight.placeholder; + return result; + } + + /** + * Creates a debounced function that delays invoking `func` until after `wait` + * milliseconds have elapsed since the last time the debounced function was + * invoked. The debounced function comes with a `cancel` method to cancel + * delayed `func` invocations and a `flush` method to immediately invoke them. + * Provide an options object to indicate whether `func` should be invoked on + * the leading and/or trailing edge of the `wait` timeout. The `func` is invoked + * with the last arguments provided to the debounced function. Subsequent calls + * to the debounced function return the result of the last `func` invocation. + * + * **Note:** If `leading` and `trailing` options are `true`, `func` is invoked + * on the trailing edge of the timeout only if the debounced function is + * invoked more than once during the `wait` timeout. + * + * See [David Corbacho's article](http://drupalmotion.com/article/debounce-and-throttle-visual-explanation) + * for details over the differences between `_.debounce` and `_.throttle`. + * + * @static + * @memberOf _ + * @category Function + * @param {Function} func The function to debounce. + * @param {number} [wait=0] The number of milliseconds to delay. + * @param {Object} [options] The options object. + * @param {boolean} [options.leading=false] Specify invoking on the leading + * edge of the timeout. + * @param {number} [options.maxWait] The maximum time `func` is allowed to be + * delayed before it's invoked. + * @param {boolean} [options.trailing=true] Specify invoking on the trailing + * edge of the timeout. + * @returns {Function} Returns the new debounced function. + * @example + * + * // Avoid costly calculations while the window size is in flux. + * jQuery(window).on('resize', _.debounce(calculateLayout, 150)); + * + * // Invoke `sendMail` when clicked, debouncing subsequent calls. + * jQuery(element).on('click', _.debounce(sendMail, 300, { + * 'leading': true, + * 'trailing': false + * })); + * + * // Ensure `batchLog` is invoked once after 1 second of debounced calls. + * var debounced = _.debounce(batchLog, 250, { 'maxWait': 1000 }); + * var source = new EventSource('/stream'); + * jQuery(source).on('message', debounced); + * + * // Cancel the trailing debounced invocation. + * jQuery(window).on('popstate', debounced.cancel); + */ + function debounce(func, wait, options) { + var args, + maxTimeoutId, + result, + stamp, + thisArg, + timeoutId, + trailingCall, + lastCalled = 0, + leading = false, + maxWait = false, + trailing = true; + + if (typeof func != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + wait = toNumber(wait) || 0; + if (isObject(options)) { + leading = !!options.leading; + maxWait = 'maxWait' in options && nativeMax(toNumber(options.maxWait) || 0, wait); + trailing = 'trailing' in options ? !!options.trailing : trailing; + } + + function cancel() { + if (timeoutId) { + clearTimeout(timeoutId); + } + if (maxTimeoutId) { + clearTimeout(maxTimeoutId); + } + lastCalled = 0; + args = maxTimeoutId = thisArg = timeoutId = trailingCall = undefined; + } + + function complete(isCalled, id) { + if (id) { + clearTimeout(id); + } + maxTimeoutId = timeoutId = trailingCall = undefined; + if (isCalled) { + lastCalled = now(); + result = func.apply(thisArg, args); + if (!timeoutId && !maxTimeoutId) { + args = thisArg = undefined; + } + } + } + + function delayed() { + var remaining = wait - (now() - stamp); + if (remaining <= 0 || remaining > wait) { + complete(trailingCall, maxTimeoutId); + } else { + timeoutId = setTimeout(delayed, remaining); + } + } + + function flush() { + if ((timeoutId && trailingCall) || (maxTimeoutId && trailing)) { + result = func.apply(thisArg, args); + } + cancel(); + return result; + } + + function maxDelayed() { + complete(trailing, timeoutId); + } + + function debounced() { + args = arguments; + stamp = now(); + thisArg = this; + trailingCall = trailing && (timeoutId || !leading); + + if (maxWait === false) { + var leadingCall = leading && !timeoutId; + } else { + if (!lastCalled && !maxTimeoutId && !leading) { + lastCalled = stamp; + } + var remaining = maxWait - (stamp - lastCalled); + + var isCalled = (remaining <= 0 || remaining > maxWait) && + (leading || maxTimeoutId); + + if (isCalled) { + if (maxTimeoutId) { + maxTimeoutId = clearTimeout(maxTimeoutId); + } + lastCalled = stamp; + result = func.apply(thisArg, args); + } + else if (!maxTimeoutId) { + maxTimeoutId = setTimeout(maxDelayed, remaining); + } + } + if (isCalled && timeoutId) { + timeoutId = clearTimeout(timeoutId); + } + else if (!timeoutId && wait !== maxWait) { + timeoutId = setTimeout(delayed, wait); + } + if (leadingCall) { + isCalled = true; + result = func.apply(thisArg, args); + } + if (isCalled && !timeoutId && !maxTimeoutId) { + args = thisArg = undefined; + } + return result; + } + debounced.cancel = cancel; + debounced.flush = flush; + return debounced; + } + + /** + * Defers invoking the `func` until the current call stack has cleared. Any + * additional arguments are provided to `func` when it's invoked. + * + * @static + * @memberOf _ + * @category Function + * @param {Function} func The function to defer. + * @param {...*} [args] The arguments to invoke `func` with. + * @returns {number} Returns the timer id. + * @example + * + * _.defer(function(text) { + * console.log(text); + * }, 'deferred'); + * // => logs 'deferred' after one or more milliseconds + */ + var defer = rest(function(func, args) { + return baseDelay(func, 1, args); + }); + + /** + * Invokes `func` after `wait` milliseconds. Any additional arguments are + * provided to `func` when it's invoked. + * + * @static + * @memberOf _ + * @category Function + * @param {Function} func The function to delay. + * @param {number} wait The number of milliseconds to delay invocation. + * @param {...*} [args] The arguments to invoke `func` with. + * @returns {number} Returns the timer id. + * @example + * + * _.delay(function(text) { + * console.log(text); + * }, 1000, 'later'); + * // => logs 'later' after one second + */ + var delay = rest(function(func, wait, args) { + return baseDelay(func, toNumber(wait) || 0, args); + }); + + /** + * Creates a function that invokes `func` with arguments reversed. + * + * @static + * @memberOf _ + * @category Function + * @param {Function} func The function to flip arguments for. + * @returns {Function} Returns the new function. + * @example + * + * var flipped = _.flip(function() { + * return _.toArray(arguments); + * }); + * + * flipped('a', 'b', 'c', 'd'); + * // => ['d', 'c', 'b', 'a'] + */ + function flip(func) { + return createWrapper(func, FLIP_FLAG); + } + + /** + * Creates a function that memoizes the result of `func`. If `resolver` is + * provided it determines the cache key for storing the result based on the + * arguments provided to the memoized function. By default, the first argument + * provided to the memoized function is used as the map cache key. The `func` + * is invoked with the `this` binding of the memoized function. + * + * **Note:** The cache is exposed as the `cache` property on the memoized + * function. Its creation may be customized by replacing the `_.memoize.Cache` + * constructor with one whose instances implement the [`Map`](http://ecma-international.org/ecma-262/6.0/#sec-properties-of-the-map-prototype-object) + * method interface of `delete`, `get`, `has`, and `set`. + * + * @static + * @memberOf _ + * @category Function + * @param {Function} func The function to have its output memoized. + * @param {Function} [resolver] The function to resolve the cache key. + * @returns {Function} Returns the new memoizing function. + * @example + * + * var object = { 'a': 1, 'b': 2 }; + * var other = { 'c': 3, 'd': 4 }; + * + * var values = _.memoize(_.values); + * values(object); + * // => [1, 2] + * + * values(other); + * // => [3, 4] + * + * object.a = 2; + * values(object); + * // => [1, 2] + * + * // Modify the result cache. + * values.cache.set(object, ['a', 'b']); + * values(object); + * // => ['a', 'b'] + * + * // Replace `_.memoize.Cache`. + * _.memoize.Cache = WeakMap; + */ + function memoize(func, resolver) { + if (typeof func != 'function' || (resolver && typeof resolver != 'function')) { + throw new TypeError(FUNC_ERROR_TEXT); + } + var memoized = function() { + var args = arguments, + key = resolver ? resolver.apply(this, args) : args[0], + cache = memoized.cache; + + if (cache.has(key)) { + return cache.get(key); + } + var result = func.apply(this, args); + memoized.cache = cache.set(key, result); + return result; + }; + memoized.cache = new memoize.Cache; + return memoized; + } + + /** + * Creates a function that negates the result of the predicate `func`. The + * `func` predicate is invoked with the `this` binding and arguments of the + * created function. + * + * @static + * @memberOf _ + * @category Function + * @param {Function} predicate The predicate to negate. + * @returns {Function} Returns the new function. + * @example + * + * function isEven(n) { + * return n % 2 == 0; + * } + * + * _.filter([1, 2, 3, 4, 5, 6], _.negate(isEven)); + * // => [1, 3, 5] + */ + function negate(predicate) { + if (typeof predicate != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + return function() { + return !predicate.apply(this, arguments); + }; + } + + /** + * Creates a function that is restricted to invoking `func` once. Repeat calls + * to the function return the value of the first invocation. The `func` is + * invoked with the `this` binding and arguments of the created function. + * + * @static + * @memberOf _ + * @category Function + * @param {Function} func The function to restrict. + * @returns {Function} Returns the new restricted function. + * @example + * + * var initialize = _.once(createApplication); + * initialize(); + * initialize(); + * // `initialize` invokes `createApplication` once + */ + function once(func) { + return before(2, func); + } + + /** + * Creates a function that invokes `func` with arguments transformed by + * corresponding `transforms`. + * + * @static + * @memberOf _ + * @category Function + * @param {Function} func The function to wrap. + * @param {...(Function|Function[])} [transforms] The functions to transform + * arguments, specified individually or in arrays. + * @returns {Function} Returns the new function. + * @example + * + * function doubled(n) { + * return n * 2; + * } + * + * function square(n) { + * return n * n; + * } + * + * var func = _.overArgs(function(x, y) { + * return [x, y]; + * }, square, doubled); + * + * func(9, 3); + * // => [81, 6] + * + * func(10, 5); + * // => [100, 10] + */ + var overArgs = rest(function(func, transforms) { + transforms = arrayMap(baseFlatten(transforms, 1), getIteratee()); + + var funcsLength = transforms.length; + return rest(function(args) { + var index = -1, + length = nativeMin(args.length, funcsLength); + + while (++index < length) { + args[index] = transforms[index].call(this, args[index]); + } + return apply(func, this, args); + }); + }); + + /** + * Creates a function that invokes `func` with `partial` arguments prepended + * to those provided to the new function. This method is like `_.bind` except + * it does **not** alter the `this` binding. + * + * The `_.partial.placeholder` value, which defaults to `_` in monolithic + * builds, may be used as a placeholder for partially applied arguments. + * + * **Note:** This method doesn't set the "length" property of partially + * applied functions. + * + * @static + * @memberOf _ + * @category Function + * @param {Function} func The function to partially apply arguments to. + * @param {...*} [partials] The arguments to be partially applied. + * @returns {Function} Returns the new partially applied function. + * @example + * + * var greet = function(greeting, name) { + * return greeting + ' ' + name; + * }; + * + * var sayHelloTo = _.partial(greet, 'hello'); + * sayHelloTo('fred'); + * // => 'hello fred' + * + * // Partially applied with placeholders. + * var greetFred = _.partial(greet, _, 'fred'); + * greetFred('hi'); + * // => 'hi fred' + */ + var partial = rest(function(func, partials) { + var holders = replaceHolders(partials, getPlaceholder(partial)); + return createWrapper(func, PARTIAL_FLAG, undefined, partials, holders); + }); + + /** + * This method is like `_.partial` except that partially applied arguments + * are appended to those provided to the new function. + * + * The `_.partialRight.placeholder` value, which defaults to `_` in monolithic + * builds, may be used as a placeholder for partially applied arguments. + * + * **Note:** This method doesn't set the "length" property of partially + * applied functions. + * + * @static + * @memberOf _ + * @category Function + * @param {Function} func The function to partially apply arguments to. + * @param {...*} [partials] The arguments to be partially applied. + * @returns {Function} Returns the new partially applied function. + * @example + * + * var greet = function(greeting, name) { + * return greeting + ' ' + name; + * }; + * + * var greetFred = _.partialRight(greet, 'fred'); + * greetFred('hi'); + * // => 'hi fred' + * + * // Partially applied with placeholders. + * var sayHelloTo = _.partialRight(greet, 'hello', _); + * sayHelloTo('fred'); + * // => 'hello fred' + */ + var partialRight = rest(function(func, partials) { + var holders = replaceHolders(partials, getPlaceholder(partialRight)); + return createWrapper(func, PARTIAL_RIGHT_FLAG, undefined, partials, holders); + }); + + /** + * Creates a function that invokes `func` with arguments arranged according + * to the specified indexes where the argument value at the first index is + * provided as the first argument, the argument value at the second index is + * provided as the second argument, and so on. + * + * @static + * @memberOf _ + * @category Function + * @param {Function} func The function to rearrange arguments for. + * @param {...(number|number[])} indexes The arranged argument indexes, + * specified individually or in arrays. + * @returns {Function} Returns the new function. + * @example + * + * var rearged = _.rearg(function(a, b, c) { + * return [a, b, c]; + * }, 2, 0, 1); + * + * rearged('b', 'c', 'a') + * // => ['a', 'b', 'c'] + */ + var rearg = rest(function(func, indexes) { + return createWrapper(func, REARG_FLAG, undefined, undefined, undefined, baseFlatten(indexes, 1)); + }); + + /** + * Creates a function that invokes `func` with the `this` binding of the + * created function and arguments from `start` and beyond provided as an array. + * + * **Note:** This method is based on the [rest parameter](https://mdn.io/rest_parameters). + * + * @static + * @memberOf _ + * @category Function + * @param {Function} func The function to apply a rest parameter to. + * @param {number} [start=func.length-1] The start position of the rest parameter. + * @returns {Function} Returns the new function. + * @example + * + * var say = _.rest(function(what, names) { + * return what + ' ' + _.initial(names).join(', ') + + * (_.size(names) > 1 ? ', & ' : '') + _.last(names); + * }); + * + * say('hello', 'fred', 'barney', 'pebbles'); + * // => 'hello fred, barney, & pebbles' + */ + function rest(func, start) { + if (typeof func != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + start = nativeMax(start === undefined ? (func.length - 1) : toInteger(start), 0); + return function() { + var args = arguments, + index = -1, + length = nativeMax(args.length - start, 0), + array = Array(length); + + while (++index < length) { + array[index] = args[start + index]; + } + switch (start) { + case 0: return func.call(this, array); + case 1: return func.call(this, args[0], array); + case 2: return func.call(this, args[0], args[1], array); + } + var otherArgs = Array(start + 1); + index = -1; + while (++index < start) { + otherArgs[index] = args[index]; + } + otherArgs[start] = array; + return apply(func, this, otherArgs); + }; + } + + /** + * Creates a function that invokes `func` with the `this` binding of the created + * function and an array of arguments much like [`Function#apply`](https://es5.github.io/#x15.3.4.3). + * + * **Note:** This method is based on the [spread operator](https://mdn.io/spread_operator). + * + * @static + * @memberOf _ + * @category Function + * @param {Function} func The function to spread arguments over. + * @param {number} [start=0] The start position of the spread. + * @returns {Function} Returns the new function. + * @example + * + * var say = _.spread(function(who, what) { + * return who + ' says ' + what; + * }); + * + * say(['fred', 'hello']); + * // => 'fred says hello' + * + * var numbers = Promise.all([ + * Promise.resolve(40), + * Promise.resolve(36) + * ]); + * + * numbers.then(_.spread(function(x, y) { + * return x + y; + * })); + * // => a Promise of 76 + */ + function spread(func, start) { + if (typeof func != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + start = start === undefined ? 0 : nativeMax(toInteger(start), 0); + return rest(function(args) { + var array = args[start], + otherArgs = args.slice(0, start); + + if (array) { + arrayPush(otherArgs, array); + } + return apply(func, this, otherArgs); + }); + } + + /** + * Creates a throttled function that only invokes `func` at most once per + * every `wait` milliseconds. The throttled function comes with a `cancel` + * method to cancel delayed `func` invocations and a `flush` method to + * immediately invoke them. Provide an options object to indicate whether + * `func` should be invoked on the leading and/or trailing edge of the `wait` + * timeout. The `func` is invoked with the last arguments provided to the + * throttled function. Subsequent calls to the throttled function return the + * result of the last `func` invocation. + * + * **Note:** If `leading` and `trailing` options are `true`, `func` is invoked + * on the trailing edge of the timeout only if the throttled function is + * invoked more than once during the `wait` timeout. + * + * See [David Corbacho's article](http://drupalmotion.com/article/debounce-and-throttle-visual-explanation) + * for details over the differences between `_.throttle` and `_.debounce`. + * + * @static + * @memberOf _ + * @category Function + * @param {Function} func The function to throttle. + * @param {number} [wait=0] The number of milliseconds to throttle invocations to. + * @param {Object} [options] The options object. + * @param {boolean} [options.leading=true] Specify invoking on the leading + * edge of the timeout. + * @param {boolean} [options.trailing=true] Specify invoking on the trailing + * edge of the timeout. + * @returns {Function} Returns the new throttled function. + * @example + * + * // Avoid excessively updating the position while scrolling. + * jQuery(window).on('scroll', _.throttle(updatePosition, 100)); + * + * // Invoke `renewToken` when the click event is fired, but not more than once every 5 minutes. + * var throttled = _.throttle(renewToken, 300000, { 'trailing': false }); + * jQuery(element).on('click', throttled); + * + * // Cancel the trailing throttled invocation. + * jQuery(window).on('popstate', throttled.cancel); + */ + function throttle(func, wait, options) { + var leading = true, + trailing = true; + + if (typeof func != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + if (isObject(options)) { + leading = 'leading' in options ? !!options.leading : leading; + trailing = 'trailing' in options ? !!options.trailing : trailing; + } + return debounce(func, wait, { + 'leading': leading, + 'maxWait': wait, + 'trailing': trailing + }); + } + + /** + * Creates a function that accepts up to one argument, ignoring any + * additional arguments. + * + * @static + * @memberOf _ + * @category Function + * @param {Function} func The function to cap arguments for. + * @returns {Function} Returns the new function. + * @example + * + * _.map(['6', '8', '10'], _.unary(parseInt)); + * // => [6, 8, 10] + */ + function unary(func) { + return ary(func, 1); + } + + /** + * Creates a function that provides `value` to the wrapper function as its + * first argument. Any additional arguments provided to the function are + * appended to those provided to the wrapper function. The wrapper is invoked + * with the `this` binding of the created function. + * + * @static + * @memberOf _ + * @category Function + * @param {*} value The value to wrap. + * @param {Function} [wrapper=identity] The wrapper function. + * @returns {Function} Returns the new function. + * @example + * + * var p = _.wrap(_.escape, function(func, text) { + * return '<p>' + func(text) + '</p>'; + * }); + * + * p('fred, barney, & pebbles'); + * // => '<p>fred, barney, & pebbles</p>' + */ + function wrap(value, wrapper) { + wrapper = wrapper == null ? identity : wrapper; + return partial(wrapper, value); + } + + /*------------------------------------------------------------------------*/ + + /** + * Casts `value` as an array if it's not one. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to inspect. + * @returns {Array} Returns the cast array. + * @example + * + * _.castArray(1); + * // => [1] + * + * _.castArray({ 'a': 1 }); + * // => [{ 'a': 1 }] + * + * _.castArray('abc'); + * // => ['abc'] + * + * _.castArray(null); + * // => [null] + * + * _.castArray(undefined); + * // => [undefined] + * + * _.castArray(); + * // => [] + * + * var array = [1, 2, 3]; + * console.log(_.castArray(array) === array); + * // => true + */ + function castArray() { + if (!arguments.length) { + return []; + } + var value = arguments[0]; + return isArray(value) ? value : [value]; + } + + /** + * Creates a shallow clone of `value`. + * + * **Note:** This method is loosely based on the + * [structured clone algorithm](https://mdn.io/Structured_clone_algorithm) + * and supports cloning arrays, array buffers, booleans, date objects, maps, + * numbers, `Object` objects, regexes, sets, strings, symbols, and typed + * arrays. The own enumerable properties of `arguments` objects are cloned + * as plain objects. An empty object is returned for uncloneable values such + * as error objects, functions, DOM nodes, and WeakMaps. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to clone. + * @returns {*} Returns the cloned value. + * @example + * + * var objects = [{ 'a': 1 }, { 'b': 2 }]; + * + * var shallow = _.clone(objects); + * console.log(shallow[0] === objects[0]); + * // => true + */ + function clone(value) { + return baseClone(value); + } + + /** + * This method is like `_.clone` except that it accepts `customizer` which + * is invoked to produce the cloned value. If `customizer` returns `undefined` + * cloning is handled by the method instead. The `customizer` is invoked with + * up to four arguments; (value [, index|key, object, stack]). + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to clone. + * @param {Function} [customizer] The function to customize cloning. + * @returns {*} Returns the cloned value. + * @example + * + * function customizer(value) { + * if (_.isElement(value)) { + * return value.cloneNode(false); + * } + * } + * + * var el = _.cloneWith(document.body, customizer); + * + * console.log(el === document.body); + * // => false + * console.log(el.nodeName); + * // => 'BODY' + * console.log(el.childNodes.length); + * // => 0 + */ + function cloneWith(value, customizer) { + return baseClone(value, false, customizer); + } + + /** + * This method is like `_.clone` except that it recursively clones `value`. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to recursively clone. + * @returns {*} Returns the deep cloned value. + * @example + * + * var objects = [{ 'a': 1 }, { 'b': 2 }]; + * + * var deep = _.cloneDeep(objects); + * console.log(deep[0] === objects[0]); + * // => false + */ + function cloneDeep(value) { + return baseClone(value, true); + } + + /** + * This method is like `_.cloneWith` except that it recursively clones `value`. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to recursively clone. + * @param {Function} [customizer] The function to customize cloning. + * @returns {*} Returns the deep cloned value. + * @example + * + * function customizer(value) { + * if (_.isElement(value)) { + * return value.cloneNode(true); + * } + * } + * + * var el = _.cloneDeepWith(document.body, customizer); + * + * console.log(el === document.body); + * // => false + * console.log(el.nodeName); + * // => 'BODY' + * console.log(el.childNodes.length); + * // => 20 + */ + function cloneDeepWith(value, customizer) { + return baseClone(value, true, customizer); + } + + /** + * Performs a [`SameValueZero`](http://ecma-international.org/ecma-262/6.0/#sec-samevaluezero) + * comparison between two values to determine if they are equivalent. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @returns {boolean} Returns `true` if the values are equivalent, else `false`. + * @example + * + * var object = { 'user': 'fred' }; + * var other = { 'user': 'fred' }; + * + * _.eq(object, object); + * // => true + * + * _.eq(object, other); + * // => false + * + * _.eq('a', 'a'); + * // => true + * + * _.eq('a', Object('a')); + * // => false + * + * _.eq(NaN, NaN); + * // => true + */ + function eq(value, other) { + return value === other || (value !== value && other !== other); + } + + /** + * Checks if `value` is greater than `other`. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @returns {boolean} Returns `true` if `value` is greater than `other`, else `false`. + * @example + * + * _.gt(3, 1); + * // => true + * + * _.gt(3, 3); + * // => false + * + * _.gt(1, 3); + * // => false + */ + function gt(value, other) { + return value > other; + } + + /** + * Checks if `value` is greater than or equal to `other`. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @returns {boolean} Returns `true` if `value` is greater than or equal to `other`, else `false`. + * @example + * + * _.gte(3, 1); + * // => true + * + * _.gte(3, 3); + * // => true + * + * _.gte(1, 3); + * // => false + */ + function gte(value, other) { + return value >= other; + } + + /** + * Checks if `value` is likely an `arguments` object. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is correctly classified, else `false`. + * @example + * + * _.isArguments(function() { return arguments; }()); + * // => true + * + * _.isArguments([1, 2, 3]); + * // => false + */ + function isArguments(value) { + // Safari 8.1 incorrectly makes `arguments.callee` enumerable in strict mode. + return isArrayLikeObject(value) && hasOwnProperty.call(value, 'callee') && + (!propertyIsEnumerable.call(value, 'callee') || objectToString.call(value) == argsTag); + } + + /** + * Checks if `value` is classified as an `Array` object. + * + * @static + * @memberOf _ + * @type {Function} + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is correctly classified, else `false`. + * @example + * + * _.isArray([1, 2, 3]); + * // => true + * + * _.isArray(document.body.children); + * // => false + * + * _.isArray('abc'); + * // => false + * + * _.isArray(_.noop); + * // => false + */ + var isArray = Array.isArray; + + /** + * Checks if `value` is classified as an `ArrayBuffer` object. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is correctly classified, else `false`. + * @example + * + * _.isArrayBuffer(new ArrayBuffer(2)); + * // => true + * + * _.isArrayBuffer(new Array(2)); + * // => false + */ + function isArrayBuffer(value) { + return isObjectLike(value) && objectToString.call(value) == arrayBufferTag; + } + + /** + * Checks if `value` is array-like. A value is considered array-like if it's + * not a function and has a `value.length` that's an integer greater than or + * equal to `0` and less than or equal to `Number.MAX_SAFE_INTEGER`. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is array-like, else `false`. + * @example + * + * _.isArrayLike([1, 2, 3]); + * // => true + * + * _.isArrayLike(document.body.children); + * // => true + * + * _.isArrayLike('abc'); + * // => true + * + * _.isArrayLike(_.noop); + * // => false + */ + function isArrayLike(value) { + return value != null && + !(typeof value == 'function' && isFunction(value)) && isLength(getLength(value)); + } + + /** + * This method is like `_.isArrayLike` except that it also checks if `value` + * is an object. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is an array-like object, else `false`. + * @example + * + * _.isArrayLikeObject([1, 2, 3]); + * // => true + * + * _.isArrayLikeObject(document.body.children); + * // => true + * + * _.isArrayLikeObject('abc'); + * // => false + * + * _.isArrayLikeObject(_.noop); + * // => false + */ + function isArrayLikeObject(value) { + return isObjectLike(value) && isArrayLike(value); + } + + /** + * Checks if `value` is classified as a boolean primitive or object. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is correctly classified, else `false`. + * @example + * + * _.isBoolean(false); + * // => true + * + * _.isBoolean(null); + * // => false + */ + function isBoolean(value) { + return value === true || value === false || + (isObjectLike(value) && objectToString.call(value) == boolTag); + } + + /** + * Checks if `value` is a buffer. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a buffer, else `false`. + * @example + * + * _.isBuffer(new Buffer(2)); + * // => true + * + * _.isBuffer(new Uint8Array(2)); + * // => false + */ + var isBuffer = !Buffer ? constant(false) : function(value) { + return value instanceof Buffer; + }; + + /** + * Checks if `value` is classified as a `Date` object. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is correctly classified, else `false`. + * @example + * + * _.isDate(new Date); + * // => true + * + * _.isDate('Mon April 23 2012'); + * // => false + */ + function isDate(value) { + return isObjectLike(value) && objectToString.call(value) == dateTag; + } + + /** + * Checks if `value` is likely a DOM element. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a DOM element, else `false`. + * @example + * + * _.isElement(document.body); + * // => true + * + * _.isElement('<body>'); + * // => false + */ + function isElement(value) { + return !!value && value.nodeType === 1 && isObjectLike(value) && !isPlainObject(value); + } + + /** + * Checks if `value` is empty. A value is considered empty unless it's an + * `arguments` object, array, string, or jQuery-like collection with a length + * greater than `0` or an object with own enumerable properties. + * + * @static + * @memberOf _ + * @category Lang + * @param {Array|Object|string} value The value to inspect. + * @returns {boolean} Returns `true` if `value` is empty, else `false`. + * @example + * + * _.isEmpty(null); + * // => true + * + * _.isEmpty(true); + * // => true + * + * _.isEmpty(1); + * // => true + * + * _.isEmpty([1, 2, 3]); + * // => false + * + * _.isEmpty({ 'a': 1 }); + * // => false + */ + function isEmpty(value) { + if (isArrayLike(value) && + (isArray(value) || isString(value) || + isFunction(value.splice) || isArguments(value))) { + return !value.length; + } + for (var key in value) { + if (hasOwnProperty.call(value, key)) { + return false; + } + } + return true; + } + + /** + * Performs a deep comparison between two values to determine if they are + * equivalent. + * + * **Note:** This method supports comparing arrays, array buffers, booleans, + * date objects, error objects, maps, numbers, `Object` objects, regexes, + * sets, strings, symbols, and typed arrays. `Object` objects are compared + * by their own, not inherited, enumerable properties. Functions and DOM + * nodes are **not** supported. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @returns {boolean} Returns `true` if the values are equivalent, else `false`. + * @example + * + * var object = { 'user': 'fred' }; + * var other = { 'user': 'fred' }; + * + * _.isEqual(object, other); + * // => true + * + * object === other; + * // => false + */ + function isEqual(value, other) { + return baseIsEqual(value, other); + } + + /** + * This method is like `_.isEqual` except that it accepts `customizer` which + * is invoked to compare values. If `customizer` returns `undefined` comparisons + * are handled by the method instead. The `customizer` is invoked with up to + * six arguments: (objValue, othValue [, index|key, object, other, stack]). + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @param {Function} [customizer] The function to customize comparisons. + * @returns {boolean} Returns `true` if the values are equivalent, else `false`. + * @example + * + * function isGreeting(value) { + * return /^h(?:i|ello)$/.test(value); + * } + * + * function customizer(objValue, othValue) { + * if (isGreeting(objValue) && isGreeting(othValue)) { + * return true; + * } + * } + * + * var array = ['hello', 'goodbye']; + * var other = ['hi', 'goodbye']; + * + * _.isEqualWith(array, other, customizer); + * // => true + */ + function isEqualWith(value, other, customizer) { + customizer = typeof customizer == 'function' ? customizer : undefined; + var result = customizer ? customizer(value, other) : undefined; + return result === undefined ? baseIsEqual(value, other, customizer) : !!result; + } + + /** + * Checks if `value` is an `Error`, `EvalError`, `RangeError`, `ReferenceError`, + * `SyntaxError`, `TypeError`, or `URIError` object. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is an error object, else `false`. + * @example + * + * _.isError(new Error); + * // => true + * + * _.isError(Error); + * // => false + */ + function isError(value) { + if (!isObjectLike(value)) { + return false; + } + return (objectToString.call(value) == errorTag) || + (typeof value.message == 'string' && typeof value.name == 'string'); + } + + /** + * Checks if `value` is a finite primitive number. + * + * **Note:** This method is based on [`Number.isFinite`](https://mdn.io/Number/isFinite). + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a finite number, else `false`. + * @example + * + * _.isFinite(3); + * // => true + * + * _.isFinite(Number.MAX_VALUE); + * // => true + * + * _.isFinite(3.14); + * // => true + * + * _.isFinite(Infinity); + * // => false + */ + function isFinite(value) { + return typeof value == 'number' && nativeIsFinite(value); + } + + /** + * Checks if `value` is classified as a `Function` object. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is correctly classified, else `false`. + * @example + * + * _.isFunction(_); + * // => true + * + * _.isFunction(/abc/); + * // => false + */ + function isFunction(value) { + // The use of `Object#toString` avoids issues with the `typeof` operator + // in Safari 8 which returns 'object' for typed array constructors, and + // PhantomJS 1.9 which returns 'function' for `NodeList` instances. + var tag = isObject(value) ? objectToString.call(value) : ''; + return tag == funcTag || tag == genTag; + } + + /** + * Checks if `value` is an integer. + * + * **Note:** This method is based on [`Number.isInteger`](https://mdn.io/Number/isInteger). + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is an integer, else `false`. + * @example + * + * _.isInteger(3); + * // => true + * + * _.isInteger(Number.MIN_VALUE); + * // => false + * + * _.isInteger(Infinity); + * // => false + * + * _.isInteger('3'); + * // => false + */ + function isInteger(value) { + return typeof value == 'number' && value == toInteger(value); + } + + /** + * Checks if `value` is a valid array-like length. + * + * **Note:** This function is loosely based on [`ToLength`](http://ecma-international.org/ecma-262/6.0/#sec-tolength). + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a valid length, else `false`. + * @example + * + * _.isLength(3); + * // => true + * + * _.isLength(Number.MIN_VALUE); + * // => false + * + * _.isLength(Infinity); + * // => false + * + * _.isLength('3'); + * // => false + */ + function isLength(value) { + return typeof value == 'number' && + value > -1 && value % 1 == 0 && value <= MAX_SAFE_INTEGER; + } + + /** + * Checks if `value` is the [language type](https://es5.github.io/#x8) of `Object`. + * (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`) + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is an object, else `false`. + * @example + * + * _.isObject({}); + * // => true + * + * _.isObject([1, 2, 3]); + * // => true + * + * _.isObject(_.noop); + * // => true + * + * _.isObject(null); + * // => false + */ + function isObject(value) { + var type = typeof value; + return !!value && (type == 'object' || type == 'function'); + } + + /** + * Checks if `value` is object-like. A value is object-like if it's not `null` + * and has a `typeof` result of "object". + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is object-like, else `false`. + * @example + * + * _.isObjectLike({}); + * // => true + * + * _.isObjectLike([1, 2, 3]); + * // => true + * + * _.isObjectLike(_.noop); + * // => false + * + * _.isObjectLike(null); + * // => false + */ + function isObjectLike(value) { + return !!value && typeof value == 'object'; + } + + /** + * Checks if `value` is classified as a `Map` object. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is correctly classified, else `false`. + * @example + * + * _.isMap(new Map); + * // => true + * + * _.isMap(new WeakMap); + * // => false + */ + function isMap(value) { + return isObjectLike(value) && getTag(value) == mapTag; + } + + /** + * Performs a partial deep comparison between `object` and `source` to + * determine if `object` contains equivalent property values. This method is + * equivalent to a `_.matches` function when `source` is partially applied. + * + * **Note:** This method supports comparing the same values as `_.isEqual`. + * + * @static + * @memberOf _ + * @category Lang + * @param {Object} object The object to inspect. + * @param {Object} source The object of property values to match. + * @returns {boolean} Returns `true` if `object` is a match, else `false`. + * @example + * + * var object = { 'user': 'fred', 'age': 40 }; + * + * _.isMatch(object, { 'age': 40 }); + * // => true + * + * _.isMatch(object, { 'age': 36 }); + * // => false + */ + function isMatch(object, source) { + return object === source || baseIsMatch(object, source, getMatchData(source)); + } + + /** + * This method is like `_.isMatch` except that it accepts `customizer` which + * is invoked to compare values. If `customizer` returns `undefined` comparisons + * are handled by the method instead. The `customizer` is invoked with five + * arguments: (objValue, srcValue, index|key, object, source). + * + * @static + * @memberOf _ + * @category Lang + * @param {Object} object The object to inspect. + * @param {Object} source The object of property values to match. + * @param {Function} [customizer] The function to customize comparisons. + * @returns {boolean} Returns `true` if `object` is a match, else `false`. + * @example + * + * function isGreeting(value) { + * return /^h(?:i|ello)$/.test(value); + * } + * + * function customizer(objValue, srcValue) { + * if (isGreeting(objValue) && isGreeting(srcValue)) { + * return true; + * } + * } + * + * var object = { 'greeting': 'hello' }; + * var source = { 'greeting': 'hi' }; + * + * _.isMatchWith(object, source, customizer); + * // => true + */ + function isMatchWith(object, source, customizer) { + customizer = typeof customizer == 'function' ? customizer : undefined; + return baseIsMatch(object, source, getMatchData(source), customizer); + } + + /** + * Checks if `value` is `NaN`. + * + * **Note:** This method is not the same as [`isNaN`](https://es5.github.io/#x15.1.2.4) + * which returns `true` for `undefined` and other non-numeric values. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is `NaN`, else `false`. + * @example + * + * _.isNaN(NaN); + * // => true + * + * _.isNaN(new Number(NaN)); + * // => true + * + * isNaN(undefined); + * // => true + * + * _.isNaN(undefined); + * // => false + */ + function isNaN(value) { + // An `NaN` primitive is the only value that is not equal to itself. + // Perform the `toStringTag` check first to avoid errors with some ActiveX objects in IE. + return isNumber(value) && value != +value; + } + + /** + * Checks if `value` is a native function. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a native function, else `false`. + * @example + * + * _.isNative(Array.prototype.push); + * // => true + * + * _.isNative(_); + * // => false + */ + function isNative(value) { + if (value == null) { + return false; + } + if (isFunction(value)) { + return reIsNative.test(funcToString.call(value)); + } + return isObjectLike(value) && + (isHostObject(value) ? reIsNative : reIsHostCtor).test(value); + } + + /** + * Checks if `value` is `null`. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is `null`, else `false`. + * @example + * + * _.isNull(null); + * // => true + * + * _.isNull(void 0); + * // => false + */ + function isNull(value) { + return value === null; + } + + /** + * Checks if `value` is `null` or `undefined`. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is nullish, else `false`. + * @example + * + * _.isNil(null); + * // => true + * + * _.isNil(void 0); + * // => true + * + * _.isNil(NaN); + * // => false + */ + function isNil(value) { + return value == null; + } + + /** + * Checks if `value` is classified as a `Number` primitive or object. + * + * **Note:** To exclude `Infinity`, `-Infinity`, and `NaN`, which are classified + * as numbers, use the `_.isFinite` method. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is correctly classified, else `false`. + * @example + * + * _.isNumber(3); + * // => true + * + * _.isNumber(Number.MIN_VALUE); + * // => true + * + * _.isNumber(Infinity); + * // => true + * + * _.isNumber('3'); + * // => false + */ + function isNumber(value) { + return typeof value == 'number' || + (isObjectLike(value) && objectToString.call(value) == numberTag); + } + + /** + * Checks if `value` is a plain object, that is, an object created by the + * `Object` constructor or one with a `[[Prototype]]` of `null`. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a plain object, else `false`. + * @example + * + * function Foo() { + * this.a = 1; + * } + * + * _.isPlainObject(new Foo); + * // => false + * + * _.isPlainObject([1, 2, 3]); + * // => false + * + * _.isPlainObject({ 'x': 0, 'y': 0 }); + * // => true + * + * _.isPlainObject(Object.create(null)); + * // => true + */ + function isPlainObject(value) { + if (!isObjectLike(value) || + objectToString.call(value) != objectTag || isHostObject(value)) { + return false; + } + var proto = getPrototypeOf(value); + if (proto === null) { + return true; + } + var Ctor = proto.constructor; + return (typeof Ctor == 'function' && + Ctor instanceof Ctor && funcToString.call(Ctor) == objectCtorString); + } + + /** + * Checks if `value` is classified as a `RegExp` object. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is correctly classified, else `false`. + * @example + * + * _.isRegExp(/abc/); + * // => true + * + * _.isRegExp('/abc/'); + * // => false + */ + function isRegExp(value) { + return isObject(value) && objectToString.call(value) == regexpTag; + } + + /** + * Checks if `value` is a safe integer. An integer is safe if it's an IEEE-754 + * double precision number which isn't the result of a rounded unsafe integer. + * + * **Note:** This method is based on [`Number.isSafeInteger`](https://mdn.io/Number/isSafeInteger). + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a safe integer, else `false`. + * @example + * + * _.isSafeInteger(3); + * // => true + * + * _.isSafeInteger(Number.MIN_VALUE); + * // => false + * + * _.isSafeInteger(Infinity); + * // => false + * + * _.isSafeInteger('3'); + * // => false + */ + function isSafeInteger(value) { + return isInteger(value) && value >= -MAX_SAFE_INTEGER && value <= MAX_SAFE_INTEGER; + } + + /** + * Checks if `value` is classified as a `Set` object. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is correctly classified, else `false`. + * @example + * + * _.isSet(new Set); + * // => true + * + * _.isSet(new WeakSet); + * // => false + */ + function isSet(value) { + return isObjectLike(value) && getTag(value) == setTag; + } + + /** + * Checks if `value` is classified as a `String` primitive or object. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is correctly classified, else `false`. + * @example + * + * _.isString('abc'); + * // => true + * + * _.isString(1); + * // => false + */ + function isString(value) { + return typeof value == 'string' || + (!isArray(value) && isObjectLike(value) && objectToString.call(value) == stringTag); + } + + /** + * Checks if `value` is classified as a `Symbol` primitive or object. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is correctly classified, else `false`. + * @example + * + * _.isSymbol(Symbol.iterator); + * // => true + * + * _.isSymbol('abc'); + * // => false + */ + function isSymbol(value) { + return typeof value == 'symbol' || + (isObjectLike(value) && objectToString.call(value) == symbolTag); + } + + /** + * Checks if `value` is classified as a typed array. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is correctly classified, else `false`. + * @example + * + * _.isTypedArray(new Uint8Array); + * // => true + * + * _.isTypedArray([]); + * // => false + */ + function isTypedArray(value) { + return isObjectLike(value) && + isLength(value.length) && !!typedArrayTags[objectToString.call(value)]; + } + + /** + * Checks if `value` is `undefined`. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is `undefined`, else `false`. + * @example + * + * _.isUndefined(void 0); + * // => true + * + * _.isUndefined(null); + * // => false + */ + function isUndefined(value) { + return value === undefined; + } + + /** + * Checks if `value` is classified as a `WeakMap` object. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is correctly classified, else `false`. + * @example + * + * _.isWeakMap(new WeakMap); + * // => true + * + * _.isWeakMap(new Map); + * // => false + */ + function isWeakMap(value) { + return isObjectLike(value) && getTag(value) == weakMapTag; + } + + /** + * Checks if `value` is classified as a `WeakSet` object. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is correctly classified, else `false`. + * @example + * + * _.isWeakSet(new WeakSet); + * // => true + * + * _.isWeakSet(new Set); + * // => false + */ + function isWeakSet(value) { + return isObjectLike(value) && objectToString.call(value) == weakSetTag; + } + + /** + * Checks if `value` is less than `other`. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @returns {boolean} Returns `true` if `value` is less than `other`, else `false`. + * @example + * + * _.lt(1, 3); + * // => true + * + * _.lt(3, 3); + * // => false + * + * _.lt(3, 1); + * // => false + */ + function lt(value, other) { + return value < other; + } + + /** + * Checks if `value` is less than or equal to `other`. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @returns {boolean} Returns `true` if `value` is less than or equal to `other`, else `false`. + * @example + * + * _.lte(1, 3); + * // => true + * + * _.lte(3, 3); + * // => true + * + * _.lte(3, 1); + * // => false + */ + function lte(value, other) { + return value <= other; + } + + /** + * Converts `value` to an array. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to convert. + * @returns {Array} Returns the converted array. + * @example + * + * _.toArray({ 'a': 1, 'b': 2 }); + * // => [1, 2] + * + * _.toArray('abc'); + * // => ['a', 'b', 'c'] + * + * _.toArray(1); + * // => [] + * + * _.toArray(null); + * // => [] + */ + function toArray(value) { + if (!value) { + return []; + } + if (isArrayLike(value)) { + return isString(value) ? stringToArray(value) : copyArray(value); + } + if (iteratorSymbol && value[iteratorSymbol]) { + return iteratorToArray(value[iteratorSymbol]()); + } + var tag = getTag(value), + func = tag == mapTag ? mapToArray : (tag == setTag ? setToArray : values); + + return func(value); + } + + /** + * Converts `value` to an integer. + * + * **Note:** This function is loosely based on [`ToInteger`](http://www.ecma-international.org/ecma-262/6.0/#sec-tointeger). + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to convert. + * @returns {number} Returns the converted integer. + * @example + * + * _.toInteger(3); + * // => 3 + * + * _.toInteger(Number.MIN_VALUE); + * // => 0 + * + * _.toInteger(Infinity); + * // => 1.7976931348623157e+308 + * + * _.toInteger('3'); + * // => 3 + */ + function toInteger(value) { + if (!value) { + return value === 0 ? value : 0; + } + value = toNumber(value); + if (value === INFINITY || value === -INFINITY) { + var sign = (value < 0 ? -1 : 1); + return sign * MAX_INTEGER; + } + var remainder = value % 1; + return value === value ? (remainder ? value - remainder : value) : 0; + } + + /** + * Converts `value` to an integer suitable for use as the length of an + * array-like object. + * + * **Note:** This method is based on [`ToLength`](http://ecma-international.org/ecma-262/6.0/#sec-tolength). + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to convert. + * @returns {number} Returns the converted integer. + * @example + * + * _.toLength(3); + * // => 3 + * + * _.toLength(Number.MIN_VALUE); + * // => 0 + * + * _.toLength(Infinity); + * // => 4294967295 + * + * _.toLength('3'); + * // => 3 + */ + function toLength(value) { + return value ? baseClamp(toInteger(value), 0, MAX_ARRAY_LENGTH) : 0; + } + + /** + * Converts `value` to a number. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to process. + * @returns {number} Returns the number. + * @example + * + * _.toNumber(3); + * // => 3 + * + * _.toNumber(Number.MIN_VALUE); + * // => 5e-324 + * + * _.toNumber(Infinity); + * // => Infinity + * + * _.toNumber('3'); + * // => 3 + */ + function toNumber(value) { + if (isObject(value)) { + var other = isFunction(value.valueOf) ? value.valueOf() : value; + value = isObject(other) ? (other + '') : other; + } + if (typeof value != 'string') { + return value === 0 ? value : +value; + } + value = value.replace(reTrim, ''); + var isBinary = reIsBinary.test(value); + return (isBinary || reIsOctal.test(value)) + ? freeParseInt(value.slice(2), isBinary ? 2 : 8) + : (reIsBadHex.test(value) ? NAN : +value); + } + + /** + * Converts `value` to a plain object flattening inherited enumerable + * properties of `value` to own properties of the plain object. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to convert. + * @returns {Object} Returns the converted plain object. + * @example + * + * function Foo() { + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.assign({ 'a': 1 }, new Foo); + * // => { 'a': 1, 'b': 2 } + * + * _.assign({ 'a': 1 }, _.toPlainObject(new Foo)); + * // => { 'a': 1, 'b': 2, 'c': 3 } + */ + function toPlainObject(value) { + return copyObject(value, keysIn(value)); + } + + /** + * Converts `value` to a safe integer. A safe integer can be compared and + * represented correctly. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to convert. + * @returns {number} Returns the converted integer. + * @example + * + * _.toSafeInteger(3); + * // => 3 + * + * _.toSafeInteger(Number.MIN_VALUE); + * // => 0 + * + * _.toSafeInteger(Infinity); + * // => 9007199254740991 + * + * _.toSafeInteger('3'); + * // => 3 + */ + function toSafeInteger(value) { + return baseClamp(toInteger(value), -MAX_SAFE_INTEGER, MAX_SAFE_INTEGER); + } + + /** + * Converts `value` to a string if it's not one. An empty string is returned + * for `null` and `undefined` values. The sign of `-0` is preserved. + * + * @static + * @memberOf _ + * @category Lang + * @param {*} value The value to process. + * @returns {string} Returns the string. + * @example + * + * _.toString(null); + * // => '' + * + * _.toString(-0); + * // => '-0' + * + * _.toString([1, 2, 3]); + * // => '1,2,3' + */ + function toString(value) { + // Exit early for strings to avoid a performance hit in some environments. + if (typeof value == 'string') { + return value; + } + if (value == null) { + return ''; + } + if (isSymbol(value)) { + return Symbol ? symbolToString.call(value) : ''; + } + var result = (value + ''); + return (result == '0' && (1 / value) == -INFINITY) ? '-0' : result; + } + + /*------------------------------------------------------------------------*/ + + /** + * Assigns own enumerable properties of source objects to the destination + * object. Source objects are applied from left to right. Subsequent sources + * overwrite property assignments of previous sources. + * + * **Note:** This method mutates `object` and is loosely based on + * [`Object.assign`](https://mdn.io/Object/assign). + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The destination object. + * @param {...Object} [sources] The source objects. + * @returns {Object} Returns `object`. + * @example + * + * function Foo() { + * this.c = 3; + * } + * + * function Bar() { + * this.e = 5; + * } + * + * Foo.prototype.d = 4; + * Bar.prototype.f = 6; + * + * _.assign({ 'a': 1 }, new Foo, new Bar); + * // => { 'a': 1, 'c': 3, 'e': 5 } + */ + var assign = createAssigner(function(object, source) { + copyObject(source, keys(source), object); + }); + + /** + * This method is like `_.assign` except that it iterates over own and + * inherited source properties. + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @alias extend + * @category Object + * @param {Object} object The destination object. + * @param {...Object} [sources] The source objects. + * @returns {Object} Returns `object`. + * @example + * + * function Foo() { + * this.b = 2; + * } + * + * function Bar() { + * this.d = 4; + * } + * + * Foo.prototype.c = 3; + * Bar.prototype.e = 5; + * + * _.assignIn({ 'a': 1 }, new Foo, new Bar); + * // => { 'a': 1, 'b': 2, 'c': 3, 'd': 4, 'e': 5 } + */ + var assignIn = createAssigner(function(object, source) { + copyObject(source, keysIn(source), object); + }); + + /** + * This method is like `_.assignIn` except that it accepts `customizer` which + * is invoked to produce the assigned values. If `customizer` returns `undefined` + * assignment is handled by the method instead. The `customizer` is invoked + * with five arguments: (objValue, srcValue, key, object, source). + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @alias extendWith + * @category Object + * @param {Object} object The destination object. + * @param {...Object} sources The source objects. + * @param {Function} [customizer] The function to customize assigned values. + * @returns {Object} Returns `object`. + * @example + * + * function customizer(objValue, srcValue) { + * return _.isUndefined(objValue) ? srcValue : objValue; + * } + * + * var defaults = _.partialRight(_.assignInWith, customizer); + * + * defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 }); + * // => { 'a': 1, 'b': 2 } + */ + var assignInWith = createAssigner(function(object, source, srcIndex, customizer) { + copyObjectWith(source, keysIn(source), object, customizer); + }); + + /** + * This method is like `_.assign` except that it accepts `customizer` which + * is invoked to produce the assigned values. If `customizer` returns `undefined` + * assignment is handled by the method instead. The `customizer` is invoked + * with five arguments: (objValue, srcValue, key, object, source). + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The destination object. + * @param {...Object} sources The source objects. + * @param {Function} [customizer] The function to customize assigned values. + * @returns {Object} Returns `object`. + * @example + * + * function customizer(objValue, srcValue) { + * return _.isUndefined(objValue) ? srcValue : objValue; + * } + * + * var defaults = _.partialRight(_.assignWith, customizer); + * + * defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 }); + * // => { 'a': 1, 'b': 2 } + */ + var assignWith = createAssigner(function(object, source, srcIndex, customizer) { + copyObjectWith(source, keys(source), object, customizer); + }); + + /** + * Creates an array of values corresponding to `paths` of `object`. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to iterate over. + * @param {...(string|string[])} [paths] The property paths of elements to pick, + * specified individually or in arrays. + * @returns {Array} Returns the new array of picked elements. + * @example + * + * var object = { 'a': [{ 'b': { 'c': 3 } }, 4] }; + * + * _.at(object, ['a[0].b.c', 'a[1]']); + * // => [3, 4] + * + * _.at(['a', 'b', 'c'], 0, 2); + * // => ['a', 'c'] + */ + var at = rest(function(object, paths) { + return baseAt(object, baseFlatten(paths, 1)); + }); + + /** + * Creates an object that inherits from the `prototype` object. If a `properties` + * object is given its own enumerable properties are assigned to the created object. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} prototype The object to inherit from. + * @param {Object} [properties] The properties to assign to the object. + * @returns {Object} Returns the new object. + * @example + * + * function Shape() { + * this.x = 0; + * this.y = 0; + * } + * + * function Circle() { + * Shape.call(this); + * } + * + * Circle.prototype = _.create(Shape.prototype, { + * 'constructor': Circle + * }); + * + * var circle = new Circle; + * circle instanceof Circle; + * // => true + * + * circle instanceof Shape; + * // => true + */ + function create(prototype, properties) { + var result = baseCreate(prototype); + return properties ? baseAssign(result, properties) : result; + } + + /** + * Assigns own and inherited enumerable properties of source objects to the + * destination object for all destination properties that resolve to `undefined`. + * Source objects are applied from left to right. Once a property is set, + * additional values of the same property are ignored. + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The destination object. + * @param {...Object} [sources] The source objects. + * @returns {Object} Returns `object`. + * @example + * + * _.defaults({ 'user': 'barney' }, { 'age': 36 }, { 'user': 'fred' }); + * // => { 'user': 'barney', 'age': 36 } + */ + var defaults = rest(function(args) { + args.push(undefined, assignInDefaults); + return apply(assignInWith, undefined, args); + }); + + /** + * This method is like `_.defaults` except that it recursively assigns + * default properties. + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The destination object. + * @param {...Object} [sources] The source objects. + * @returns {Object} Returns `object`. + * @example + * + * _.defaultsDeep({ 'user': { 'name': 'barney' } }, { 'user': { 'name': 'fred', 'age': 36 } }); + * // => { 'user': { 'name': 'barney', 'age': 36 } } + * + */ + var defaultsDeep = rest(function(args) { + args.push(undefined, mergeDefaults); + return apply(mergeWith, undefined, args); + }); + + /** + * This method is like `_.find` except that it returns the key of the first + * element `predicate` returns truthy for instead of the element itself. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to search. + * @param {Function|Object|string} [predicate=_.identity] The function invoked per iteration. + * @returns {string|undefined} Returns the key of the matched element, else `undefined`. + * @example + * + * var users = { + * 'barney': { 'age': 36, 'active': true }, + * 'fred': { 'age': 40, 'active': false }, + * 'pebbles': { 'age': 1, 'active': true } + * }; + * + * _.findKey(users, function(o) { return o.age < 40; }); + * // => 'barney' (iteration order is not guaranteed) + * + * // The `_.matches` iteratee shorthand. + * _.findKey(users, { 'age': 1, 'active': true }); + * // => 'pebbles' + * + * // The `_.matchesProperty` iteratee shorthand. + * _.findKey(users, ['active', false]); + * // => 'fred' + * + * // The `_.property` iteratee shorthand. + * _.findKey(users, 'active'); + * // => 'barney' + */ + function findKey(object, predicate) { + return baseFind(object, getIteratee(predicate, 3), baseForOwn, true); + } + + /** + * This method is like `_.findKey` except that it iterates over elements of + * a collection in the opposite order. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to search. + * @param {Function|Object|string} [predicate=_.identity] The function invoked per iteration. + * @returns {string|undefined} Returns the key of the matched element, else `undefined`. + * @example + * + * var users = { + * 'barney': { 'age': 36, 'active': true }, + * 'fred': { 'age': 40, 'active': false }, + * 'pebbles': { 'age': 1, 'active': true } + * }; + * + * _.findLastKey(users, function(o) { return o.age < 40; }); + * // => returns 'pebbles' assuming `_.findKey` returns 'barney' + * + * // The `_.matches` iteratee shorthand. + * _.findLastKey(users, { 'age': 36, 'active': true }); + * // => 'barney' + * + * // The `_.matchesProperty` iteratee shorthand. + * _.findLastKey(users, ['active', false]); + * // => 'fred' + * + * // The `_.property` iteratee shorthand. + * _.findLastKey(users, 'active'); + * // => 'pebbles' + */ + function findLastKey(object, predicate) { + return baseFind(object, getIteratee(predicate, 3), baseForOwnRight, true); + } + + /** + * Iterates over own and inherited enumerable properties of an object invoking + * `iteratee` for each property. The iteratee is invoked with three arguments: + * (value, key, object). Iteratee functions may exit iteration early by explicitly + * returning `false`. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @returns {Object} Returns `object`. + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.forIn(new Foo, function(value, key) { + * console.log(key); + * }); + * // => logs 'a', 'b', then 'c' (iteration order is not guaranteed) + */ + function forIn(object, iteratee) { + return object == null + ? object + : baseFor(object, baseCastFunction(iteratee), keysIn); + } + + /** + * This method is like `_.forIn` except that it iterates over properties of + * `object` in the opposite order. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @returns {Object} Returns `object`. + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.forInRight(new Foo, function(value, key) { + * console.log(key); + * }); + * // => logs 'c', 'b', then 'a' assuming `_.forIn` logs 'a', 'b', then 'c' + */ + function forInRight(object, iteratee) { + return object == null + ? object + : baseForRight(object, baseCastFunction(iteratee), keysIn); + } + + /** + * Iterates over own enumerable properties of an object invoking `iteratee` + * for each property. The iteratee is invoked with three arguments: + * (value, key, object). Iteratee functions may exit iteration early by + * explicitly returning `false`. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @returns {Object} Returns `object`. + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.forOwn(new Foo, function(value, key) { + * console.log(key); + * }); + * // => logs 'a' then 'b' (iteration order is not guaranteed) + */ + function forOwn(object, iteratee) { + return object && baseForOwn(object, baseCastFunction(iteratee)); + } + + /** + * This method is like `_.forOwn` except that it iterates over properties of + * `object` in the opposite order. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @returns {Object} Returns `object`. + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.forOwnRight(new Foo, function(value, key) { + * console.log(key); + * }); + * // => logs 'b' then 'a' assuming `_.forOwn` logs 'a' then 'b' + */ + function forOwnRight(object, iteratee) { + return object && baseForOwnRight(object, baseCastFunction(iteratee)); + } + + /** + * Creates an array of function property names from own enumerable properties + * of `object`. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to inspect. + * @returns {Array} Returns the new array of property names. + * @example + * + * function Foo() { + * this.a = _.constant('a'); + * this.b = _.constant('b'); + * } + * + * Foo.prototype.c = _.constant('c'); + * + * _.functions(new Foo); + * // => ['a', 'b'] + */ + function functions(object) { + return object == null ? [] : baseFunctions(object, keys(object)); + } + + /** + * Creates an array of function property names from own and inherited + * enumerable properties of `object`. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to inspect. + * @returns {Array} Returns the new array of property names. + * @example + * + * function Foo() { + * this.a = _.constant('a'); + * this.b = _.constant('b'); + * } + * + * Foo.prototype.c = _.constant('c'); + * + * _.functionsIn(new Foo); + * // => ['a', 'b', 'c'] + */ + function functionsIn(object) { + return object == null ? [] : baseFunctions(object, keysIn(object)); + } + + /** + * Gets the value at `path` of `object`. If the resolved value is + * `undefined` the `defaultValue` is used in its place. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to query. + * @param {Array|string} path The path of the property to get. + * @param {*} [defaultValue] The value returned if the resolved value is `undefined`. + * @returns {*} Returns the resolved value. + * @example + * + * var object = { 'a': [{ 'b': { 'c': 3 } }] }; + * + * _.get(object, 'a[0].b.c'); + * // => 3 + * + * _.get(object, ['a', '0', 'b', 'c']); + * // => 3 + * + * _.get(object, 'a.b.c', 'default'); + * // => 'default' + */ + function get(object, path, defaultValue) { + var result = object == null ? undefined : baseGet(object, path); + return result === undefined ? defaultValue : result; + } + + /** + * Checks if `path` is a direct property of `object`. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to query. + * @param {Array|string} path The path to check. + * @returns {boolean} Returns `true` if `path` exists, else `false`. + * @example + * + * var object = { 'a': { 'b': { 'c': 3 } } }; + * var other = _.create({ 'a': _.create({ 'b': _.create({ 'c': 3 }) }) }); + * + * _.has(object, 'a'); + * // => true + * + * _.has(object, 'a.b.c'); + * // => true + * + * _.has(object, ['a', 'b', 'c']); + * // => true + * + * _.has(other, 'a'); + * // => false + */ + function has(object, path) { + return hasPath(object, path, baseHas); + } + + /** + * Checks if `path` is a direct or inherited property of `object`. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to query. + * @param {Array|string} path The path to check. + * @returns {boolean} Returns `true` if `path` exists, else `false`. + * @example + * + * var object = _.create({ 'a': _.create({ 'b': _.create({ 'c': 3 }) }) }); + * + * _.hasIn(object, 'a'); + * // => true + * + * _.hasIn(object, 'a.b.c'); + * // => true + * + * _.hasIn(object, ['a', 'b', 'c']); + * // => true + * + * _.hasIn(object, 'b'); + * // => false + */ + function hasIn(object, path) { + return hasPath(object, path, baseHasIn); + } + + /** + * Creates an object composed of the inverted keys and values of `object`. + * If `object` contains duplicate values, subsequent values overwrite property + * assignments of previous values. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to invert. + * @returns {Object} Returns the new inverted object. + * @example + * + * var object = { 'a': 1, 'b': 2, 'c': 1 }; + * + * _.invert(object); + * // => { '1': 'c', '2': 'b' } + */ + var invert = createInverter(function(result, value, key) { + result[value] = key; + }, constant(identity)); + + /** + * This method is like `_.invert` except that the inverted object is generated + * from the results of running each element of `object` through `iteratee`. + * The corresponding inverted value of each inverted key is an array of keys + * responsible for generating the inverted value. The iteratee is invoked + * with one argument: (value). + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to invert. + * @param {Function|Object|string} [iteratee=_.identity] The iteratee invoked per element. + * @returns {Object} Returns the new inverted object. + * @example + * + * var object = { 'a': 1, 'b': 2, 'c': 1 }; + * + * _.invertBy(object); + * // => { '1': ['a', 'c'], '2': ['b'] } + * + * _.invertBy(object, function(value) { + * return 'group' + value; + * }); + * // => { 'group1': ['a', 'c'], 'group2': ['b'] } + */ + var invertBy = createInverter(function(result, value, key) { + if (hasOwnProperty.call(result, value)) { + result[value].push(key); + } else { + result[value] = [key]; + } + }, getIteratee); + + /** + * Invokes the method at `path` of `object`. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to query. + * @param {Array|string} path The path of the method to invoke. + * @param {...*} [args] The arguments to invoke the method with. + * @returns {*} Returns the result of the invoked method. + * @example + * + * var object = { 'a': [{ 'b': { 'c': [1, 2, 3, 4] } }] }; + * + * _.invoke(object, 'a[0].b.c.slice', 1, 3); + * // => [2, 3] + */ + var invoke = rest(baseInvoke); + + /** + * Creates an array of the own enumerable property names of `object`. + * + * **Note:** Non-object values are coerced to objects. See the + * [ES spec](http://ecma-international.org/ecma-262/6.0/#sec-object.keys) + * for more details. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to query. + * @returns {Array} Returns the array of property names. + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.keys(new Foo); + * // => ['a', 'b'] (iteration order is not guaranteed) + * + * _.keys('hi'); + * // => ['0', '1'] + */ + function keys(object) { + var isProto = isPrototype(object); + if (!(isProto || isArrayLike(object))) { + return baseKeys(object); + } + var indexes = indexKeys(object), + skipIndexes = !!indexes, + result = indexes || [], + length = result.length; + + for (var key in object) { + if (baseHas(object, key) && + !(skipIndexes && (key == 'length' || isIndex(key, length))) && + !(isProto && key == 'constructor')) { + result.push(key); + } + } + return result; + } + + /** + * Creates an array of the own and inherited enumerable property names of `object`. + * + * **Note:** Non-object values are coerced to objects. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to query. + * @returns {Array} Returns the array of property names. + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.keysIn(new Foo); + * // => ['a', 'b', 'c'] (iteration order is not guaranteed) + */ + function keysIn(object) { + var index = -1, + isProto = isPrototype(object), + props = baseKeysIn(object), + propsLength = props.length, + indexes = indexKeys(object), + skipIndexes = !!indexes, + result = indexes || [], + length = result.length; + + while (++index < propsLength) { + var key = props[index]; + if (!(skipIndexes && (key == 'length' || isIndex(key, length))) && + !(key == 'constructor' && (isProto || !hasOwnProperty.call(object, key)))) { + result.push(key); + } + } + return result; + } + + /** + * The opposite of `_.mapValues`; this method creates an object with the + * same values as `object` and keys generated by running each own enumerable + * property of `object` through `iteratee`. The iteratee is invoked with + * three arguments: (value, key, object). + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to iterate over. + * @param {Function|Object|string} [iteratee=_.identity] The function invoked per iteration. + * @returns {Object} Returns the new mapped object. + * @example + * + * _.mapKeys({ 'a': 1, 'b': 2 }, function(value, key) { + * return key + value; + * }); + * // => { 'a1': 1, 'b2': 2 } + */ + function mapKeys(object, iteratee) { + var result = {}; + iteratee = getIteratee(iteratee, 3); + + baseForOwn(object, function(value, key, object) { + result[iteratee(value, key, object)] = value; + }); + return result; + } + + /** + * Creates an object with the same keys as `object` and values generated by + * running each own enumerable property of `object` through `iteratee`. The + * iteratee is invoked with three arguments: (value, key, object). + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to iterate over. + * @param {Function|Object|string} [iteratee=_.identity] The function invoked per iteration. + * @returns {Object} Returns the new mapped object. + * @example + * + * var users = { + * 'fred': { 'user': 'fred', 'age': 40 }, + * 'pebbles': { 'user': 'pebbles', 'age': 1 } + * }; + * + * _.mapValues(users, function(o) { return o.age; }); + * // => { 'fred': 40, 'pebbles': 1 } (iteration order is not guaranteed) + * + * // The `_.property` iteratee shorthand. + * _.mapValues(users, 'age'); + * // => { 'fred': 40, 'pebbles': 1 } (iteration order is not guaranteed) + */ + function mapValues(object, iteratee) { + var result = {}; + iteratee = getIteratee(iteratee, 3); + + baseForOwn(object, function(value, key, object) { + result[key] = iteratee(value, key, object); + }); + return result; + } + + /** + * Recursively merges own and inherited enumerable properties of source objects + * into the destination object. Source properties that resolve to `undefined` + * are skipped if a destination value exists. Array and plain object properties + * are merged recursively. Other objects and value types are overridden by + * assignment. Source objects are applied from left to right. Subsequent + * sources overwrite property assignments of previous sources. + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The destination object. + * @param {...Object} [sources] The source objects. + * @returns {Object} Returns `object`. + * @example + * + * var users = { + * 'data': [{ 'user': 'barney' }, { 'user': 'fred' }] + * }; + * + * var ages = { + * 'data': [{ 'age': 36 }, { 'age': 40 }] + * }; + * + * _.merge(users, ages); + * // => { 'data': [{ 'user': 'barney', 'age': 36 }, { 'user': 'fred', 'age': 40 }] } + */ + var merge = createAssigner(function(object, source, srcIndex) { + baseMerge(object, source, srcIndex); + }); + + /** + * This method is like `_.merge` except that it accepts `customizer` which + * is invoked to produce the merged values of the destination and source + * properties. If `customizer` returns `undefined` merging is handled by the + * method instead. The `customizer` is invoked with seven arguments: + * (objValue, srcValue, key, object, source, stack). + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The destination object. + * @param {...Object} sources The source objects. + * @param {Function} customizer The function to customize assigned values. + * @returns {Object} Returns `object`. + * @example + * + * function customizer(objValue, srcValue) { + * if (_.isArray(objValue)) { + * return objValue.concat(srcValue); + * } + * } + * + * var object = { + * 'fruits': ['apple'], + * 'vegetables': ['beet'] + * }; + * + * var other = { + * 'fruits': ['banana'], + * 'vegetables': ['carrot'] + * }; + * + * _.mergeWith(object, other, customizer); + * // => { 'fruits': ['apple', 'banana'], 'vegetables': ['beet', 'carrot'] } + */ + var mergeWith = createAssigner(function(object, source, srcIndex, customizer) { + baseMerge(object, source, srcIndex, customizer); + }); + + /** + * The opposite of `_.pick`; this method creates an object composed of the + * own and inherited enumerable properties of `object` that are not omitted. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The source object. + * @param {...(string|string[])} [props] The property names to omit, specified + * individually or in arrays. + * @returns {Object} Returns the new object. + * @example + * + * var object = { 'a': 1, 'b': '2', 'c': 3 }; + * + * _.omit(object, ['a', 'c']); + * // => { 'b': '2' } + */ + var omit = rest(function(object, props) { + if (object == null) { + return {}; + } + props = arrayMap(baseFlatten(props, 1), String); + return basePick(object, baseDifference(keysIn(object), props)); + }); + + /** + * The opposite of `_.pickBy`; this method creates an object composed of + * the own and inherited enumerable properties of `object` that `predicate` + * doesn't return truthy for. The predicate is invoked with two arguments: + * (value, key). + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The source object. + * @param {Function|Object|string} [predicate=_.identity] The function invoked per property. + * @returns {Object} Returns the new object. + * @example + * + * var object = { 'a': 1, 'b': '2', 'c': 3 }; + * + * _.omitBy(object, _.isNumber); + * // => { 'b': '2' } + */ + function omitBy(object, predicate) { + predicate = getIteratee(predicate); + return basePickBy(object, function(value, key) { + return !predicate(value, key); + }); + } + + /** + * Creates an object composed of the picked `object` properties. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The source object. + * @param {...(string|string[])} [props] The property names to pick, specified + * individually or in arrays. + * @returns {Object} Returns the new object. + * @example + * + * var object = { 'a': 1, 'b': '2', 'c': 3 }; + * + * _.pick(object, ['a', 'c']); + * // => { 'a': 1, 'c': 3 } + */ + var pick = rest(function(object, props) { + return object == null ? {} : basePick(object, baseFlatten(props, 1)); + }); + + /** + * Creates an object composed of the `object` properties `predicate` returns + * truthy for. The predicate is invoked with two arguments: (value, key). + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The source object. + * @param {Function|Object|string} [predicate=_.identity] The function invoked per property. + * @returns {Object} Returns the new object. + * @example + * + * var object = { 'a': 1, 'b': '2', 'c': 3 }; + * + * _.pickBy(object, _.isNumber); + * // => { 'a': 1, 'c': 3 } + */ + function pickBy(object, predicate) { + return object == null ? {} : basePickBy(object, getIteratee(predicate)); + } + + /** + * This method is like `_.get` except that if the resolved value is a function + * it's invoked with the `this` binding of its parent object and its result + * is returned. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to query. + * @param {Array|string} path The path of the property to resolve. + * @param {*} [defaultValue] The value returned if the resolved value is `undefined`. + * @returns {*} Returns the resolved value. + * @example + * + * var object = { 'a': [{ 'b': { 'c1': 3, 'c2': _.constant(4) } }] }; + * + * _.result(object, 'a[0].b.c1'); + * // => 3 + * + * _.result(object, 'a[0].b.c2'); + * // => 4 + * + * _.result(object, 'a[0].b.c3', 'default'); + * // => 'default' + * + * _.result(object, 'a[0].b.c3', _.constant('default')); + * // => 'default' + */ + function result(object, path, defaultValue) { + if (!isKey(path, object)) { + path = baseCastPath(path); + var result = get(object, path); + object = parent(object, path); + } else { + result = object == null ? undefined : object[path]; + } + if (result === undefined) { + result = defaultValue; + } + return isFunction(result) ? result.call(object) : result; + } + + /** + * Sets the value at `path` of `object`. If a portion of `path` doesn't exist + * it's created. Arrays are created for missing index properties while objects + * are created for all other missing properties. Use `_.setWith` to customize + * `path` creation. + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to modify. + * @param {Array|string} path The path of the property to set. + * @param {*} value The value to set. + * @returns {Object} Returns `object`. + * @example + * + * var object = { 'a': [{ 'b': { 'c': 3 } }] }; + * + * _.set(object, 'a[0].b.c', 4); + * console.log(object.a[0].b.c); + * // => 4 + * + * _.set(object, 'x[0].y.z', 5); + * console.log(object.x[0].y.z); + * // => 5 + */ + function set(object, path, value) { + return object == null ? object : baseSet(object, path, value); + } + + /** + * This method is like `_.set` except that it accepts `customizer` which is + * invoked to produce the objects of `path`. If `customizer` returns `undefined` + * path creation is handled by the method instead. The `customizer` is invoked + * with three arguments: (nsValue, key, nsObject). + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to modify. + * @param {Array|string} path The path of the property to set. + * @param {*} value The value to set. + * @param {Function} [customizer] The function to customize assigned values. + * @returns {Object} Returns `object`. + * @example + * + * _.setWith({ '0': { 'length': 2 } }, '[0][1][2]', 3, Object); + * // => { '0': { '1': { '2': 3 }, 'length': 2 } } + */ + function setWith(object, path, value, customizer) { + customizer = typeof customizer == 'function' ? customizer : undefined; + return object == null ? object : baseSet(object, path, value, customizer); + } + + /** + * Creates an array of own enumerable key-value pairs for `object` which + * can be consumed by `_.fromPairs`. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to query. + * @returns {Array} Returns the new array of key-value pairs. + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.toPairs(new Foo); + * // => [['a', 1], ['b', 2]] (iteration order is not guaranteed) + */ + function toPairs(object) { + return baseToPairs(object, keys(object)); + } + + /** + * Creates an array of own and inherited enumerable key-value pairs for + * `object` which can be consumed by `_.fromPairs`. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to query. + * @returns {Array} Returns the new array of key-value pairs. + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.toPairsIn(new Foo); + * // => [['a', 1], ['b', 2], ['c', 1]] (iteration order is not guaranteed) + */ + function toPairsIn(object) { + return baseToPairs(object, keysIn(object)); + } + + /** + * An alternative to `_.reduce`; this method transforms `object` to a new + * `accumulator` object which is the result of running each of its own enumerable + * properties through `iteratee`, with each invocation potentially mutating + * the `accumulator` object. The iteratee is invoked with four arguments: + * (accumulator, value, key, object). Iteratee functions may exit iteration + * early by explicitly returning `false`. + * + * @static + * @memberOf _ + * @category Object + * @param {Array|Object} object The object to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @param {*} [accumulator] The custom accumulator value. + * @returns {*} Returns the accumulated value. + * @example + * + * _.transform([2, 3, 4], function(result, n) { + * result.push(n *= n); + * return n % 2 == 0; + * }, []); + * // => [4, 9] + * + * _.transform({ 'a': 1, 'b': 2, 'c': 1 }, function(result, value, key) { + * (result[value] || (result[value] = [])).push(key); + * }, {}); + * // => { '1': ['a', 'c'], '2': ['b'] } + */ + function transform(object, iteratee, accumulator) { + var isArr = isArray(object) || isTypedArray(object); + iteratee = getIteratee(iteratee, 4); + + if (accumulator == null) { + if (isArr || isObject(object)) { + var Ctor = object.constructor; + if (isArr) { + accumulator = isArray(object) ? new Ctor : []; + } else { + accumulator = isFunction(Ctor) ? baseCreate(getPrototypeOf(object)) : {}; + } + } else { + accumulator = {}; + } + } + (isArr ? arrayEach : baseForOwn)(object, function(value, index, object) { + return iteratee(accumulator, value, index, object); + }); + return accumulator; + } + + /** + * Removes the property at `path` of `object`. + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to modify. + * @param {Array|string} path The path of the property to unset. + * @returns {boolean} Returns `true` if the property is deleted, else `false`. + * @example + * + * var object = { 'a': [{ 'b': { 'c': 7 } }] }; + * _.unset(object, 'a[0].b.c'); + * // => true + * + * console.log(object); + * // => { 'a': [{ 'b': {} }] }; + * + * _.unset(object, 'a[0].b.c'); + * // => true + * + * console.log(object); + * // => { 'a': [{ 'b': {} }] }; + */ + function unset(object, path) { + return object == null ? true : baseUnset(object, path); + } + + /** + * Creates an array of the own enumerable property values of `object`. + * + * **Note:** Non-object values are coerced to objects. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to query. + * @returns {Array} Returns the array of property values. + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.values(new Foo); + * // => [1, 2] (iteration order is not guaranteed) + * + * _.values('hi'); + * // => ['h', 'i'] + */ + function values(object) { + return object ? baseValues(object, keys(object)) : []; + } + + /** + * Creates an array of the own and inherited enumerable property values of `object`. + * + * **Note:** Non-object values are coerced to objects. + * + * @static + * @memberOf _ + * @category Object + * @param {Object} object The object to query. + * @returns {Array} Returns the array of property values. + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.valuesIn(new Foo); + * // => [1, 2, 3] (iteration order is not guaranteed) + */ + function valuesIn(object) { + return object == null ? [] : baseValues(object, keysIn(object)); + } + + /*------------------------------------------------------------------------*/ + + /** + * Clamps `number` within the inclusive `lower` and `upper` bounds. + * + * @static + * @memberOf _ + * @category Number + * @param {number} number The number to clamp. + * @param {number} [lower] The lower bound. + * @param {number} upper The upper bound. + * @returns {number} Returns the clamped number. + * @example + * + * _.clamp(-10, -5, 5); + * // => -5 + * + * _.clamp(10, -5, 5); + * // => 5 + */ + function clamp(number, lower, upper) { + if (upper === undefined) { + upper = lower; + lower = undefined; + } + if (upper !== undefined) { + upper = toNumber(upper); + upper = upper === upper ? upper : 0; + } + if (lower !== undefined) { + lower = toNumber(lower); + lower = lower === lower ? lower : 0; + } + return baseClamp(toNumber(number), lower, upper); + } + + /** + * Checks if `n` is between `start` and up to but not including, `end`. If + * `end` is not specified it's set to `start` with `start` then set to `0`. + * If `start` is greater than `end` the params are swapped to support + * negative ranges. + * + * @static + * @memberOf _ + * @category Number + * @param {number} number The number to check. + * @param {number} [start=0] The start of the range. + * @param {number} end The end of the range. + * @returns {boolean} Returns `true` if `number` is in the range, else `false`. + * @example + * + * _.inRange(3, 2, 4); + * // => true + * + * _.inRange(4, 8); + * // => true + * + * _.inRange(4, 2); + * // => false + * + * _.inRange(2, 2); + * // => false + * + * _.inRange(1.2, 2); + * // => true + * + * _.inRange(5.2, 4); + * // => false + * + * _.inRange(-3, -2, -6); + * // => true + */ + function inRange(number, start, end) { + start = toNumber(start) || 0; + if (end === undefined) { + end = start; + start = 0; + } else { + end = toNumber(end) || 0; + } + number = toNumber(number); + return baseInRange(number, start, end); + } + + /** + * Produces a random number between the inclusive `lower` and `upper` bounds. + * If only one argument is provided a number between `0` and the given number + * is returned. If `floating` is `true`, or either `lower` or `upper` are floats, + * a floating-point number is returned instead of an integer. + * + * **Note:** JavaScript follows the IEEE-754 standard for resolving + * floating-point values which can produce unexpected results. + * + * @static + * @memberOf _ + * @category Number + * @param {number} [lower=0] The lower bound. + * @param {number} [upper=1] The upper bound. + * @param {boolean} [floating] Specify returning a floating-point number. + * @returns {number} Returns the random number. + * @example + * + * _.random(0, 5); + * // => an integer between 0 and 5 + * + * _.random(5); + * // => also an integer between 0 and 5 + * + * _.random(5, true); + * // => a floating-point number between 0 and 5 + * + * _.random(1.2, 5.2); + * // => a floating-point number between 1.2 and 5.2 + */ + function random(lower, upper, floating) { + if (floating && typeof floating != 'boolean' && isIterateeCall(lower, upper, floating)) { + upper = floating = undefined; + } + if (floating === undefined) { + if (typeof upper == 'boolean') { + floating = upper; + upper = undefined; + } + else if (typeof lower == 'boolean') { + floating = lower; + lower = undefined; + } + } + if (lower === undefined && upper === undefined) { + lower = 0; + upper = 1; + } + else { + lower = toNumber(lower) || 0; + if (upper === undefined) { + upper = lower; + lower = 0; + } else { + upper = toNumber(upper) || 0; + } + } + if (lower > upper) { + var temp = lower; + lower = upper; + upper = temp; + } + if (floating || lower % 1 || upper % 1) { + var rand = nativeRandom(); + return nativeMin(lower + (rand * (upper - lower + freeParseFloat('1e-' + ((rand + '').length - 1)))), upper); + } + return baseRandom(lower, upper); + } + + /*------------------------------------------------------------------------*/ + + /** + * Converts `string` to [camel case](https://en.wikipedia.org/wiki/CamelCase). + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to convert. + * @returns {string} Returns the camel cased string. + * @example + * + * _.camelCase('Foo Bar'); + * // => 'fooBar' + * + * _.camelCase('--foo-bar'); + * // => 'fooBar' + * + * _.camelCase('__foo_bar__'); + * // => 'fooBar' + */ + var camelCase = createCompounder(function(result, word, index) { + word = word.toLowerCase(); + return result + (index ? capitalize(word) : word); + }); + + /** + * Converts the first character of `string` to upper case and the remaining + * to lower case. + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to capitalize. + * @returns {string} Returns the capitalized string. + * @example + * + * _.capitalize('FRED'); + * // => 'Fred' + */ + function capitalize(string) { + return upperFirst(toString(string).toLowerCase()); + } + + /** + * Deburrs `string` by converting [latin-1 supplementary letters](https://en.wikipedia.org/wiki/Latin-1_Supplement_(Unicode_block)#Character_table) + * to basic latin letters and removing [combining diacritical marks](https://en.wikipedia.org/wiki/Combining_Diacritical_Marks). + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to deburr. + * @returns {string} Returns the deburred string. + * @example + * + * _.deburr('déjà vu'); + * // => 'deja vu' + */ + function deburr(string) { + string = toString(string); + return string && string.replace(reLatin1, deburrLetter).replace(reComboMark, ''); + } + + /** + * Checks if `string` ends with the given target string. + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to search. + * @param {string} [target] The string to search for. + * @param {number} [position=string.length] The position to search from. + * @returns {boolean} Returns `true` if `string` ends with `target`, else `false`. + * @example + * + * _.endsWith('abc', 'c'); + * // => true + * + * _.endsWith('abc', 'b'); + * // => false + * + * _.endsWith('abc', 'b', 2); + * // => true + */ + function endsWith(string, target, position) { + string = toString(string); + target = typeof target == 'string' ? target : (target + ''); + + var length = string.length; + position = position === undefined + ? length + : baseClamp(toInteger(position), 0, length); + + position -= target.length; + return position >= 0 && string.indexOf(target, position) == position; + } + + /** + * Converts the characters "&", "<", ">", '"', "'", and "\`" in `string` to + * their corresponding HTML entities. + * + * **Note:** No other characters are escaped. To escape additional + * characters use a third-party library like [_he_](https://mths.be/he). + * + * Though the ">" character is escaped for symmetry, characters like + * ">" and "/" don't need escaping in HTML and have no special meaning + * unless they're part of a tag or unquoted attribute value. + * See [Mathias Bynens's article](https://mathiasbynens.be/notes/ambiguous-ampersands) + * (under "semi-related fun fact") for more details. + * + * Backticks are escaped because in IE < 9, they can break out of + * attribute values or HTML comments. See [#59](https://html5sec.org/#59), + * [#102](https://html5sec.org/#102), [#108](https://html5sec.org/#108), and + * [#133](https://html5sec.org/#133) of the [HTML5 Security Cheatsheet](https://html5sec.org/) + * for more details. + * + * When working with HTML you should always [quote attribute values](http://wonko.com/post/html-escaping) + * to reduce XSS vectors. + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to escape. + * @returns {string} Returns the escaped string. + * @example + * + * _.escape('fred, barney, & pebbles'); + * // => 'fred, barney, & pebbles' + */ + function escape(string) { + string = toString(string); + return (string && reHasUnescapedHtml.test(string)) + ? string.replace(reUnescapedHtml, escapeHtmlChar) + : string; + } + + /** + * Escapes the `RegExp` special characters "^", "$", "\", ".", "*", "+", + * "?", "(", ")", "[", "]", "{", "}", and "|" in `string`. + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to escape. + * @returns {string} Returns the escaped string. + * @example + * + * _.escapeRegExp('[lodash](https://lodash.com/)'); + * // => '\[lodash\]\(https://lodash\.com/\)' + */ + function escapeRegExp(string) { + string = toString(string); + return (string && reHasRegExpChar.test(string)) + ? string.replace(reRegExpChar, '\\$&') + : string; + } + + /** + * Converts `string` to [kebab case](https://en.wikipedia.org/wiki/Letter_case#Special_case_styles). + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to convert. + * @returns {string} Returns the kebab cased string. + * @example + * + * _.kebabCase('Foo Bar'); + * // => 'foo-bar' + * + * _.kebabCase('fooBar'); + * // => 'foo-bar' + * + * _.kebabCase('__foo_bar__'); + * // => 'foo-bar' + */ + var kebabCase = createCompounder(function(result, word, index) { + return result + (index ? '-' : '') + word.toLowerCase(); + }); + + /** + * Converts `string`, as space separated words, to lower case. + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to convert. + * @returns {string} Returns the lower cased string. + * @example + * + * _.lowerCase('--Foo-Bar'); + * // => 'foo bar' + * + * _.lowerCase('fooBar'); + * // => 'foo bar' + * + * _.lowerCase('__FOO_BAR__'); + * // => 'foo bar' + */ + var lowerCase = createCompounder(function(result, word, index) { + return result + (index ? ' ' : '') + word.toLowerCase(); + }); + + /** + * Converts the first character of `string` to lower case. + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to convert. + * @returns {string} Returns the converted string. + * @example + * + * _.lowerFirst('Fred'); + * // => 'fred' + * + * _.lowerFirst('FRED'); + * // => 'fRED' + */ + var lowerFirst = createCaseFirst('toLowerCase'); + + /** + * Converts the first character of `string` to upper case. + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to convert. + * @returns {string} Returns the converted string. + * @example + * + * _.upperFirst('fred'); + * // => 'Fred' + * + * _.upperFirst('FRED'); + * // => 'FRED' + */ + var upperFirst = createCaseFirst('toUpperCase'); + + /** + * Pads `string` on the left and right sides if it's shorter than `length`. + * Padding characters are truncated if they can't be evenly divided by `length`. + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to pad. + * @param {number} [length=0] The padding length. + * @param {string} [chars=' '] The string used as padding. + * @returns {string} Returns the padded string. + * @example + * + * _.pad('abc', 8); + * // => ' abc ' + * + * _.pad('abc', 8, '_-'); + * // => '_-abc_-_' + * + * _.pad('abc', 3); + * // => 'abc' + */ + function pad(string, length, chars) { + string = toString(string); + length = toInteger(length); + + var strLength = stringSize(string); + if (!length || strLength >= length) { + return string; + } + var mid = (length - strLength) / 2, + leftLength = nativeFloor(mid), + rightLength = nativeCeil(mid); + + return createPadding('', leftLength, chars) + string + createPadding('', rightLength, chars); + } + + /** + * Pads `string` on the right side if it's shorter than `length`. Padding + * characters are truncated if they exceed `length`. + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to pad. + * @param {number} [length=0] The padding length. + * @param {string} [chars=' '] The string used as padding. + * @returns {string} Returns the padded string. + * @example + * + * _.padEnd('abc', 6); + * // => 'abc ' + * + * _.padEnd('abc', 6, '_-'); + * // => 'abc_-_' + * + * _.padEnd('abc', 3); + * // => 'abc' + */ + function padEnd(string, length, chars) { + string = toString(string); + return string + createPadding(string, length, chars); + } + + /** + * Pads `string` on the left side if it's shorter than `length`. Padding + * characters are truncated if they exceed `length`. + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to pad. + * @param {number} [length=0] The padding length. + * @param {string} [chars=' '] The string used as padding. + * @returns {string} Returns the padded string. + * @example + * + * _.padStart('abc', 6); + * // => ' abc' + * + * _.padStart('abc', 6, '_-'); + * // => '_-_abc' + * + * _.padStart('abc', 3); + * // => 'abc' + */ + function padStart(string, length, chars) { + string = toString(string); + return createPadding(string, length, chars) + string; + } + + /** + * Converts `string` to an integer of the specified radix. If `radix` is + * `undefined` or `0`, a `radix` of `10` is used unless `value` is a hexadecimal, + * in which case a `radix` of `16` is used. + * + * **Note:** This method aligns with the [ES5 implementation](https://es5.github.io/#x15.1.2.2) + * of `parseInt`. + * + * @static + * @memberOf _ + * @category String + * @param {string} string The string to convert. + * @param {number} [radix=10] The radix to interpret `value` by. + * @param- {Object} [guard] Enables use as an iteratee for functions like `_.map`. + * @returns {number} Returns the converted integer. + * @example + * + * _.parseInt('08'); + * // => 8 + * + * _.map(['6', '08', '10'], _.parseInt); + * // => [6, 8, 10] + */ + function parseInt(string, radix, guard) { + // Chrome fails to trim leading <BOM> whitespace characters. + // See https://code.google.com/p/v8/issues/detail?id=3109 for more details. + if (guard || radix == null) { + radix = 0; + } else if (radix) { + radix = +radix; + } + string = toString(string).replace(reTrim, ''); + return nativeParseInt(string, radix || (reHasHexPrefix.test(string) ? 16 : 10)); + } + + /** + * Repeats the given string `n` times. + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to repeat. + * @param {number} [n=0] The number of times to repeat the string. + * @returns {string} Returns the repeated string. + * @example + * + * _.repeat('*', 3); + * // => '***' + * + * _.repeat('abc', 2); + * // => 'abcabc' + * + * _.repeat('abc', 0); + * // => '' + */ + function repeat(string, n) { + string = toString(string); + n = toInteger(n); + + var result = ''; + if (!string || n < 1 || n > MAX_SAFE_INTEGER) { + return result; + } + // Leverage the exponentiation by squaring algorithm for a faster repeat. + // See https://en.wikipedia.org/wiki/Exponentiation_by_squaring for more details. + do { + if (n % 2) { + result += string; + } + n = nativeFloor(n / 2); + string += string; + } while (n); + + return result; + } + + /** + * Replaces matches for `pattern` in `string` with `replacement`. + * + * **Note:** This method is based on [`String#replace`](https://mdn.io/String/replace). + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to modify. + * @param {RegExp|string} pattern The pattern to replace. + * @param {Function|string} replacement The match replacement. + * @returns {string} Returns the modified string. + * @example + * + * _.replace('Hi Fred', 'Fred', 'Barney'); + * // => 'Hi Barney' + */ + function replace() { + var args = arguments, + string = toString(args[0]); + + return args.length < 3 ? string : string.replace(args[1], args[2]); + } + + /** + * Converts `string` to [snake case](https://en.wikipedia.org/wiki/Snake_case). + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to convert. + * @returns {string} Returns the snake cased string. + * @example + * + * _.snakeCase('Foo Bar'); + * // => 'foo_bar' + * + * _.snakeCase('fooBar'); + * // => 'foo_bar' + * + * _.snakeCase('--foo-bar'); + * // => 'foo_bar' + */ + var snakeCase = createCompounder(function(result, word, index) { + return result + (index ? '_' : '') + word.toLowerCase(); + }); + + /** + * Splits `string` by `separator`. + * + * **Note:** This method is based on [`String#split`](https://mdn.io/String/split). + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to split. + * @param {RegExp|string} separator The separator pattern to split by. + * @param {number} [limit] The length to truncate results to. + * @returns {Array} Returns the new array of string segments. + * @example + * + * _.split('a-b-c', '-', 2); + * // => ['a', 'b'] + */ + function split(string, separator, limit) { + return toString(string).split(separator, limit); + } + + /** + * Converts `string` to [start case](https://en.wikipedia.org/wiki/Letter_case#Stylistic_or_specialised_usage). + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to convert. + * @returns {string} Returns the start cased string. + * @example + * + * _.startCase('--foo-bar'); + * // => 'Foo Bar' + * + * _.startCase('fooBar'); + * // => 'Foo Bar' + * + * _.startCase('__foo_bar__'); + * // => 'Foo Bar' + */ + var startCase = createCompounder(function(result, word, index) { + return result + (index ? ' ' : '') + capitalize(word); + }); + + /** + * Checks if `string` starts with the given target string. + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to search. + * @param {string} [target] The string to search for. + * @param {number} [position=0] The position to search from. + * @returns {boolean} Returns `true` if `string` starts with `target`, else `false`. + * @example + * + * _.startsWith('abc', 'a'); + * // => true + * + * _.startsWith('abc', 'b'); + * // => false + * + * _.startsWith('abc', 'b', 1); + * // => true + */ + function startsWith(string, target, position) { + string = toString(string); + position = baseClamp(toInteger(position), 0, string.length); + return string.lastIndexOf(target, position) == position; + } + + /** + * Creates a compiled template function that can interpolate data properties + * in "interpolate" delimiters, HTML-escape interpolated data properties in + * "escape" delimiters, and execute JavaScript in "evaluate" delimiters. Data + * properties may be accessed as free variables in the template. If a setting + * object is given it takes precedence over `_.templateSettings` values. + * + * **Note:** In the development build `_.template` utilizes + * [sourceURLs](http://www.html5rocks.com/en/tutorials/developertools/sourcemaps/#toc-sourceurl) + * for easier debugging. + * + * For more information on precompiling templates see + * [lodash's custom builds documentation](https://lodash.com/custom-builds). + * + * For more information on Chrome extension sandboxes see + * [Chrome's extensions documentation](https://developer.chrome.com/extensions/sandboxingEval). + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The template string. + * @param {Object} [options] The options object. + * @param {RegExp} [options.escape] The HTML "escape" delimiter. + * @param {RegExp} [options.evaluate] The "evaluate" delimiter. + * @param {Object} [options.imports] An object to import into the template as free variables. + * @param {RegExp} [options.interpolate] The "interpolate" delimiter. + * @param {string} [options.sourceURL] The sourceURL of the template's compiled source. + * @param {string} [options.variable] The data object variable name. + * @param- {Object} [guard] Enables use as an iteratee for functions like `_.map`. + * @returns {Function} Returns the compiled template function. + * @example + * + * // Use the "interpolate" delimiter to create a compiled template. + * var compiled = _.template('hello <%= user %>!'); + * compiled({ 'user': 'fred' }); + * // => 'hello fred!' + * + * // Use the HTML "escape" delimiter to escape data property values. + * var compiled = _.template('<b><%- value %></b>'); + * compiled({ 'value': '<script>' }); + * // => '<b><script></b>' + * + * // Use the "evaluate" delimiter to execute JavaScript and generate HTML. + * var compiled = _.template('<% _.forEach(users, function(user) { %><li><%- user %></li><% }); %>'); + * compiled({ 'users': ['fred', 'barney'] }); + * // => '<li>fred</li><li>barney</li>' + * + * // Use the internal `print` function in "evaluate" delimiters. + * var compiled = _.template('<% print("hello " + user); %>!'); + * compiled({ 'user': 'barney' }); + * // => 'hello barney!' + * + * // Use the ES delimiter as an alternative to the default "interpolate" delimiter. + * var compiled = _.template('hello ${ user }!'); + * compiled({ 'user': 'pebbles' }); + * // => 'hello pebbles!' + * + * // Use custom template delimiters. + * _.templateSettings.interpolate = /{{([\s\S]+?)}}/g; + * var compiled = _.template('hello {{ user }}!'); + * compiled({ 'user': 'mustache' }); + * // => 'hello mustache!' + * + * // Use backslashes to treat delimiters as plain text. + * var compiled = _.template('<%= "\\<%- value %\\>" %>'); + * compiled({ 'value': 'ignored' }); + * // => '<%- value %>' + * + * // Use the `imports` option to import `jQuery` as `jq`. + * var text = '<% jq.each(users, function(user) { %><li><%- user %></li><% }); %>'; + * var compiled = _.template(text, { 'imports': { 'jq': jQuery } }); + * compiled({ 'users': ['fred', 'barney'] }); + * // => '<li>fred</li><li>barney</li>' + * + * // Use the `sourceURL` option to specify a custom sourceURL for the template. + * var compiled = _.template('hello <%= user %>!', { 'sourceURL': '/basic/greeting.jst' }); + * compiled(data); + * // => find the source of "greeting.jst" under the Sources tab or Resources panel of the web inspector + * + * // Use the `variable` option to ensure a with-statement isn't used in the compiled template. + * var compiled = _.template('hi <%= data.user %>!', { 'variable': 'data' }); + * compiled.source; + * // => function(data) { + * // var __t, __p = ''; + * // __p += 'hi ' + ((__t = ( data.user )) == null ? '' : __t) + '!'; + * // return __p; + * // } + * + * // Use the `source` property to inline compiled templates for meaningful + * // line numbers in error messages and stack traces. + * fs.writeFileSync(path.join(cwd, 'jst.js'), '\ + * var JST = {\ + * "main": ' + _.template(mainText).source + '\ + * };\ + * '); + */ + function template(string, options, guard) { + // Based on John Resig's `tmpl` implementation (http://ejohn.org/blog/javascript-micro-templating/) + // and Laura Doktorova's doT.js (https://github.com/olado/doT). + var settings = lodash.templateSettings; + + if (guard && isIterateeCall(string, options, guard)) { + options = undefined; + } + string = toString(string); + options = assignInWith({}, options, settings, assignInDefaults); + + var imports = assignInWith({}, options.imports, settings.imports, assignInDefaults), + importsKeys = keys(imports), + importsValues = baseValues(imports, importsKeys); + + var isEscaping, + isEvaluating, + index = 0, + interpolate = options.interpolate || reNoMatch, + source = "__p += '"; + + // Compile the regexp to match each delimiter. + var reDelimiters = RegExp( + (options.escape || reNoMatch).source + '|' + + interpolate.source + '|' + + (interpolate === reInterpolate ? reEsTemplate : reNoMatch).source + '|' + + (options.evaluate || reNoMatch).source + '|$' + , 'g'); + + // Use a sourceURL for easier debugging. + var sourceURL = '//# sourceURL=' + + ('sourceURL' in options + ? options.sourceURL + : ('lodash.templateSources[' + (++templateCounter) + ']') + ) + '\n'; + + string.replace(reDelimiters, function(match, escapeValue, interpolateValue, esTemplateValue, evaluateValue, offset) { + interpolateValue || (interpolateValue = esTemplateValue); + + // Escape characters that can't be included in string literals. + source += string.slice(index, offset).replace(reUnescapedString, escapeStringChar); + + // Replace delimiters with snippets. + if (escapeValue) { + isEscaping = true; + source += "' +\n__e(" + escapeValue + ") +\n'"; + } + if (evaluateValue) { + isEvaluating = true; + source += "';\n" + evaluateValue + ";\n__p += '"; + } + if (interpolateValue) { + source += "' +\n((__t = (" + interpolateValue + ")) == null ? '' : __t) +\n'"; + } + index = offset + match.length; + + // The JS engine embedded in Adobe products needs `match` returned in + // order to produce the correct `offset` value. + return match; + }); + + source += "';\n"; + + // If `variable` is not specified wrap a with-statement around the generated + // code to add the data object to the top of the scope chain. + var variable = options.variable; + if (!variable) { + source = 'with (obj) {\n' + source + '\n}\n'; + } + // Cleanup code by stripping empty strings. + source = (isEvaluating ? source.replace(reEmptyStringLeading, '') : source) + .replace(reEmptyStringMiddle, '$1') + .replace(reEmptyStringTrailing, '$1;'); + + // Frame code as the function body. + source = 'function(' + (variable || 'obj') + ') {\n' + + (variable + ? '' + : 'obj || (obj = {});\n' + ) + + "var __t, __p = ''" + + (isEscaping + ? ', __e = _.escape' + : '' + ) + + (isEvaluating + ? ', __j = Array.prototype.join;\n' + + "function print() { __p += __j.call(arguments, '') }\n" + : ';\n' + ) + + source + + 'return __p\n}'; + + var result = attempt(function() { + return Function(importsKeys, sourceURL + 'return ' + source) + .apply(undefined, importsValues); + }); + + // Provide the compiled function's source by its `toString` method or + // the `source` property as a convenience for inlining compiled templates. + result.source = source; + if (isError(result)) { + throw result; + } + return result; + } + + /** + * Converts `string`, as a whole, to lower case. + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to convert. + * @returns {string} Returns the lower cased string. + * @example + * + * _.toLower('--Foo-Bar'); + * // => '--foo-bar' + * + * _.toLower('fooBar'); + * // => 'foobar' + * + * _.toLower('__FOO_BAR__'); + * // => '__foo_bar__' + */ + function toLower(value) { + return toString(value).toLowerCase(); + } + + /** + * Converts `string`, as a whole, to upper case. + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to convert. + * @returns {string} Returns the upper cased string. + * @example + * + * _.toUpper('--foo-bar'); + * // => '--FOO-BAR' + * + * _.toUpper('fooBar'); + * // => 'FOOBAR' + * + * _.toUpper('__foo_bar__'); + * // => '__FOO_BAR__' + */ + function toUpper(value) { + return toString(value).toUpperCase(); + } + + /** + * Removes leading and trailing whitespace or specified characters from `string`. + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to trim. + * @param {string} [chars=whitespace] The characters to trim. + * @param- {Object} [guard] Enables use as an iteratee for functions like `_.map`. + * @returns {string} Returns the trimmed string. + * @example + * + * _.trim(' abc '); + * // => 'abc' + * + * _.trim('-_-abc-_-', '_-'); + * // => 'abc' + * + * _.map([' foo ', ' bar '], _.trim); + * // => ['foo', 'bar'] + */ + function trim(string, chars, guard) { + string = toString(string); + if (!string) { + return string; + } + if (guard || chars === undefined) { + return string.replace(reTrim, ''); + } + chars = (chars + ''); + if (!chars) { + return string; + } + var strSymbols = stringToArray(string), + chrSymbols = stringToArray(chars); + + return strSymbols + .slice(charsStartIndex(strSymbols, chrSymbols), charsEndIndex(strSymbols, chrSymbols) + 1) + .join(''); + } + + /** + * Removes trailing whitespace or specified characters from `string`. + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to trim. + * @param {string} [chars=whitespace] The characters to trim. + * @param- {Object} [guard] Enables use as an iteratee for functions like `_.map`. + * @returns {string} Returns the trimmed string. + * @example + * + * _.trimEnd(' abc '); + * // => ' abc' + * + * _.trimEnd('-_-abc-_-', '_-'); + * // => '-_-abc' + */ + function trimEnd(string, chars, guard) { + string = toString(string); + if (!string) { + return string; + } + if (guard || chars === undefined) { + return string.replace(reTrimEnd, ''); + } + chars = (chars + ''); + if (!chars) { + return string; + } + var strSymbols = stringToArray(string); + return strSymbols + .slice(0, charsEndIndex(strSymbols, stringToArray(chars)) + 1) + .join(''); + } + + /** + * Removes leading whitespace or specified characters from `string`. + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to trim. + * @param {string} [chars=whitespace] The characters to trim. + * @param- {Object} [guard] Enables use as an iteratee for functions like `_.map`. + * @returns {string} Returns the trimmed string. + * @example + * + * _.trimStart(' abc '); + * // => 'abc ' + * + * _.trimStart('-_-abc-_-', '_-'); + * // => 'abc-_-' + */ + function trimStart(string, chars, guard) { + string = toString(string); + if (!string) { + return string; + } + if (guard || chars === undefined) { + return string.replace(reTrimStart, ''); + } + chars = (chars + ''); + if (!chars) { + return string; + } + var strSymbols = stringToArray(string); + return strSymbols + .slice(charsStartIndex(strSymbols, stringToArray(chars))) + .join(''); + } + + /** + * Truncates `string` if it's longer than the given maximum string length. + * The last characters of the truncated string are replaced with the omission + * string which defaults to "...". + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to truncate. + * @param {Object} [options=({})] The options object. + * @param {number} [options.length=30] The maximum string length. + * @param {string} [options.omission='...'] The string to indicate text is omitted. + * @param {RegExp|string} [options.separator] The separator pattern to truncate to. + * @returns {string} Returns the truncated string. + * @example + * + * _.truncate('hi-diddly-ho there, neighborino'); + * // => 'hi-diddly-ho there, neighbo...' + * + * _.truncate('hi-diddly-ho there, neighborino', { + * 'length': 24, + * 'separator': ' ' + * }); + * // => 'hi-diddly-ho there,...' + * + * _.truncate('hi-diddly-ho there, neighborino', { + * 'length': 24, + * 'separator': /,? +/ + * }); + * // => 'hi-diddly-ho there...' + * + * _.truncate('hi-diddly-ho there, neighborino', { + * 'omission': ' [...]' + * }); + * // => 'hi-diddly-ho there, neig [...]' + */ + function truncate(string, options) { + var length = DEFAULT_TRUNC_LENGTH, + omission = DEFAULT_TRUNC_OMISSION; + + if (isObject(options)) { + var separator = 'separator' in options ? options.separator : separator; + length = 'length' in options ? toInteger(options.length) : length; + omission = 'omission' in options ? toString(options.omission) : omission; + } + string = toString(string); + + var strLength = string.length; + if (reHasComplexSymbol.test(string)) { + var strSymbols = stringToArray(string); + strLength = strSymbols.length; + } + if (length >= strLength) { + return string; + } + var end = length - stringSize(omission); + if (end < 1) { + return omission; + } + var result = strSymbols + ? strSymbols.slice(0, end).join('') + : string.slice(0, end); + + if (separator === undefined) { + return result + omission; + } + if (strSymbols) { + end += (result.length - end); + } + if (isRegExp(separator)) { + if (string.slice(end).search(separator)) { + var match, + substring = result; + + if (!separator.global) { + separator = RegExp(separator.source, toString(reFlags.exec(separator)) + 'g'); + } + separator.lastIndex = 0; + while ((match = separator.exec(substring))) { + var newEnd = match.index; + } + result = result.slice(0, newEnd === undefined ? end : newEnd); + } + } else if (string.indexOf(separator, end) != end) { + var index = result.lastIndexOf(separator); + if (index > -1) { + result = result.slice(0, index); + } + } + return result + omission; + } + + /** + * The inverse of `_.escape`; this method converts the HTML entities + * `&`, `<`, `>`, `"`, `'`, and ``` in `string` to their + * corresponding characters. + * + * **Note:** No other HTML entities are unescaped. To unescape additional HTML + * entities use a third-party library like [_he_](https://mths.be/he). + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to unescape. + * @returns {string} Returns the unescaped string. + * @example + * + * _.unescape('fred, barney, & pebbles'); + * // => 'fred, barney, & pebbles' + */ + function unescape(string) { + string = toString(string); + return (string && reHasEscapedHtml.test(string)) + ? string.replace(reEscapedHtml, unescapeHtmlChar) + : string; + } + + /** + * Converts `string`, as space separated words, to upper case. + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to convert. + * @returns {string} Returns the upper cased string. + * @example + * + * _.upperCase('--foo-bar'); + * // => 'FOO BAR' + * + * _.upperCase('fooBar'); + * // => 'FOO BAR' + * + * _.upperCase('__foo_bar__'); + * // => 'FOO BAR' + */ + var upperCase = createCompounder(function(result, word, index) { + return result + (index ? ' ' : '') + word.toUpperCase(); + }); + + /** + * Splits `string` into an array of its words. + * + * @static + * @memberOf _ + * @category String + * @param {string} [string=''] The string to inspect. + * @param {RegExp|string} [pattern] The pattern to match words. + * @param- {Object} [guard] Enables use as an iteratee for functions like `_.map`. + * @returns {Array} Returns the words of `string`. + * @example + * + * _.words('fred, barney, & pebbles'); + * // => ['fred', 'barney', 'pebbles'] + * + * _.words('fred, barney, & pebbles', /[^, ]+/g); + * // => ['fred', 'barney', '&', 'pebbles'] + */ + function words(string, pattern, guard) { + string = toString(string); + pattern = guard ? undefined : pattern; + + if (pattern === undefined) { + pattern = reHasComplexWord.test(string) ? reComplexWord : reBasicWord; + } + return string.match(pattern) || []; + } + + /*------------------------------------------------------------------------*/ + + /** + * Attempts to invoke `func`, returning either the result or the caught error + * object. Any additional arguments are provided to `func` when it's invoked. + * + * @static + * @memberOf _ + * @category Util + * @param {Function} func The function to attempt. + * @returns {*} Returns the `func` result or error object. + * @example + * + * // Avoid throwing errors for invalid selectors. + * var elements = _.attempt(function(selector) { + * return document.querySelectorAll(selector); + * }, '>_>'); + * + * if (_.isError(elements)) { + * elements = []; + * } + */ + var attempt = rest(function(func, args) { + try { + return apply(func, undefined, args); + } catch (e) { + return isError(e) ? e : new Error(e); + } + }); + + /** + * Binds methods of an object to the object itself, overwriting the existing + * method. + * + * **Note:** This method doesn't set the "length" property of bound functions. + * + * @static + * @memberOf _ + * @category Util + * @param {Object} object The object to bind and assign the bound methods to. + * @param {...(string|string[])} methodNames The object method names to bind, + * specified individually or in arrays. + * @returns {Object} Returns `object`. + * @example + * + * var view = { + * 'label': 'docs', + * 'onClick': function() { + * console.log('clicked ' + this.label); + * } + * }; + * + * _.bindAll(view, 'onClick'); + * jQuery(element).on('click', view.onClick); + * // => logs 'clicked docs' when clicked + */ + var bindAll = rest(function(object, methodNames) { + arrayEach(baseFlatten(methodNames, 1), function(key) { + object[key] = bind(object[key], object); + }); + return object; + }); + + /** + * Creates a function that iterates over `pairs` invoking the corresponding + * function of the first predicate to return truthy. The predicate-function + * pairs are invoked with the `this` binding and arguments of the created + * function. + * + * @static + * @memberOf _ + * @category Util + * @param {Array} pairs The predicate-function pairs. + * @returns {Function} Returns the new function. + * @example + * + * var func = _.cond([ + * [_.matches({ 'a': 1 }), _.constant('matches A')], + * [_.conforms({ 'b': _.isNumber }), _.constant('matches B')], + * [_.constant(true), _.constant('no match')] + * ]); + * + * func({ 'a': 1, 'b': 2 }); + * // => 'matches A' + * + * func({ 'a': 0, 'b': 1 }); + * // => 'matches B' + * + * func({ 'a': '1', 'b': '2' }); + * // => 'no match' + */ + function cond(pairs) { + var length = pairs ? pairs.length : 0, + toIteratee = getIteratee(); + + pairs = !length ? [] : arrayMap(pairs, function(pair) { + if (typeof pair[1] != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + return [toIteratee(pair[0]), pair[1]]; + }); + + return rest(function(args) { + var index = -1; + while (++index < length) { + var pair = pairs[index]; + if (apply(pair[0], this, args)) { + return apply(pair[1], this, args); + } + } + }); + } + + /** + * Creates a function that invokes the predicate properties of `source` with + * the corresponding property values of a given object, returning `true` if + * all predicates return truthy, else `false`. + * + * @static + * @memberOf _ + * @category Util + * @param {Object} source The object of property predicates to conform to. + * @returns {Function} Returns the new function. + * @example + * + * var users = [ + * { 'user': 'barney', 'age': 36 }, + * { 'user': 'fred', 'age': 40 } + * ]; + * + * _.filter(users, _.conforms({ 'age': _.partial(_.gt, _, 38) })); + * // => [{ 'user': 'fred', 'age': 40 }] + */ + function conforms(source) { + return baseConforms(baseClone(source, true)); + } + + /** + * Creates a function that returns `value`. + * + * @static + * @memberOf _ + * @category Util + * @param {*} value The value to return from the new function. + * @returns {Function} Returns the new function. + * @example + * + * var object = { 'user': 'fred' }; + * var getter = _.constant(object); + * + * getter() === object; + * // => true + */ + function constant(value) { + return function() { + return value; + }; + } + + /** + * Creates a function that returns the result of invoking the given functions + * with the `this` binding of the created function, where each successive + * invocation is supplied the return value of the previous. + * + * @static + * @memberOf _ + * @category Util + * @param {...(Function|Function[])} [funcs] Functions to invoke. + * @returns {Function} Returns the new function. + * @example + * + * function square(n) { + * return n * n; + * } + * + * var addSquare = _.flow(_.add, square); + * addSquare(1, 2); + * // => 9 + */ + var flow = createFlow(); + + /** + * This method is like `_.flow` except that it creates a function that + * invokes the given functions from right to left. + * + * @static + * @memberOf _ + * @category Util + * @param {...(Function|Function[])} [funcs] Functions to invoke. + * @returns {Function} Returns the new function. + * @example + * + * function square(n) { + * return n * n; + * } + * + * var addSquare = _.flowRight(square, _.add); + * addSquare(1, 2); + * // => 9 + */ + var flowRight = createFlow(true); + + /** + * This method returns the first argument given to it. + * + * @static + * @memberOf _ + * @category Util + * @param {*} value Any value. + * @returns {*} Returns `value`. + * @example + * + * var object = { 'user': 'fred' }; + * + * _.identity(object) === object; + * // => true + */ + function identity(value) { + return value; + } + + /** + * Creates a function that invokes `func` with the arguments of the created + * function. If `func` is a property name the created callback returns the + * property value for a given element. If `func` is an object the created + * callback returns `true` for elements that contain the equivalent object + * properties, otherwise it returns `false`. + * + * @static + * @memberOf _ + * @category Util + * @param {*} [func=_.identity] The value to convert to a callback. + * @returns {Function} Returns the callback. + * @example + * + * var users = [ + * { 'user': 'barney', 'age': 36 }, + * { 'user': 'fred', 'age': 40 } + * ]; + * + * // Create custom iteratee shorthands. + * _.iteratee = _.wrap(_.iteratee, function(callback, func) { + * var p = /^(\S+)\s*([<>])\s*(\S+)$/.exec(func); + * return !p ? callback(func) : function(object) { + * return (p[2] == '>' ? object[p[1]] > p[3] : object[p[1]] < p[3]); + * }; + * }); + * + * _.filter(users, 'age > 36'); + * // => [{ 'user': 'fred', 'age': 40 }] + */ + function iteratee(func) { + return baseIteratee(typeof func == 'function' ? func : baseClone(func, true)); + } + + /** + * Creates a function that performs a partial deep comparison between a given + * object and `source`, returning `true` if the given object has equivalent + * property values, else `false`. The created function is equivalent to + * `_.isMatch` with a `source` partially applied. + * + * **Note:** This method supports comparing the same values as `_.isEqual`. + * + * @static + * @memberOf _ + * @category Util + * @param {Object} source The object of property values to match. + * @returns {Function} Returns the new function. + * @example + * + * var users = [ + * { 'user': 'barney', 'age': 36, 'active': true }, + * { 'user': 'fred', 'age': 40, 'active': false } + * ]; + * + * _.filter(users, _.matches({ 'age': 40, 'active': false })); + * // => [{ 'user': 'fred', 'age': 40, 'active': false }] + */ + function matches(source) { + return baseMatches(baseClone(source, true)); + } + + /** + * Creates a function that performs a partial deep comparison between the + * value at `path` of a given object to `srcValue`, returning `true` if the + * object value is equivalent, else `false`. + * + * **Note:** This method supports comparing the same values as `_.isEqual`. + * + * @static + * @memberOf _ + * @category Util + * @param {Array|string} path The path of the property to get. + * @param {*} srcValue The value to match. + * @returns {Function} Returns the new function. + * @example + * + * var users = [ + * { 'user': 'barney' }, + * { 'user': 'fred' } + * ]; + * + * _.find(users, _.matchesProperty('user', 'fred')); + * // => { 'user': 'fred' } + */ + function matchesProperty(path, srcValue) { + return baseMatchesProperty(path, baseClone(srcValue, true)); + } + + /** + * Creates a function that invokes the method at `path` of a given object. + * Any additional arguments are provided to the invoked method. + * + * @static + * @memberOf _ + * @category Util + * @param {Array|string} path The path of the method to invoke. + * @param {...*} [args] The arguments to invoke the method with. + * @returns {Function} Returns the new function. + * @example + * + * var objects = [ + * { 'a': { 'b': { 'c': _.constant(2) } } }, + * { 'a': { 'b': { 'c': _.constant(1) } } } + * ]; + * + * _.map(objects, _.method('a.b.c')); + * // => [2, 1] + * + * _.invokeMap(_.sortBy(objects, _.method(['a', 'b', 'c'])), 'a.b.c'); + * // => [1, 2] + */ + var method = rest(function(path, args) { + return function(object) { + return baseInvoke(object, path, args); + }; + }); + + /** + * The opposite of `_.method`; this method creates a function that invokes + * the method at a given path of `object`. Any additional arguments are + * provided to the invoked method. + * + * @static + * @memberOf _ + * @category Util + * @param {Object} object The object to query. + * @param {...*} [args] The arguments to invoke the method with. + * @returns {Function} Returns the new function. + * @example + * + * var array = _.times(3, _.constant), + * object = { 'a': array, 'b': array, 'c': array }; + * + * _.map(['a[2]', 'c[0]'], _.methodOf(object)); + * // => [2, 0] + * + * _.map([['a', '2'], ['c', '0']], _.methodOf(object)); + * // => [2, 0] + */ + var methodOf = rest(function(object, args) { + return function(path) { + return baseInvoke(object, path, args); + }; + }); + + /** + * Adds all own enumerable function properties of a source object to the + * destination object. If `object` is a function then methods are added to + * its prototype as well. + * + * **Note:** Use `_.runInContext` to create a pristine `lodash` function to + * avoid conflicts caused by modifying the original. + * + * @static + * @memberOf _ + * @category Util + * @param {Function|Object} [object=lodash] The destination object. + * @param {Object} source The object of functions to add. + * @param {Object} [options] The options object. + * @param {boolean} [options.chain=true] Specify whether the functions added + * are chainable. + * @returns {Function|Object} Returns `object`. + * @example + * + * function vowels(string) { + * return _.filter(string, function(v) { + * return /[aeiou]/i.test(v); + * }); + * } + * + * _.mixin({ 'vowels': vowels }); + * _.vowels('fred'); + * // => ['e'] + * + * _('fred').vowels().value(); + * // => ['e'] + * + * _.mixin({ 'vowels': vowels }, { 'chain': false }); + * _('fred').vowels(); + * // => ['e'] + */ + function mixin(object, source, options) { + var props = keys(source), + methodNames = baseFunctions(source, props); + + if (options == null && + !(isObject(source) && (methodNames.length || !props.length))) { + options = source; + source = object; + object = this; + methodNames = baseFunctions(source, keys(source)); + } + var chain = (isObject(options) && 'chain' in options) ? options.chain : true, + isFunc = isFunction(object); + + arrayEach(methodNames, function(methodName) { + var func = source[methodName]; + object[methodName] = func; + if (isFunc) { + object.prototype[methodName] = function() { + var chainAll = this.__chain__; + if (chain || chainAll) { + var result = object(this.__wrapped__), + actions = result.__actions__ = copyArray(this.__actions__); + + actions.push({ 'func': func, 'args': arguments, 'thisArg': object }); + result.__chain__ = chainAll; + return result; + } + return func.apply(object, arrayPush([this.value()], arguments)); + }; + } + }); + + return object; + } + + /** + * Reverts the `_` variable to its previous value and returns a reference to + * the `lodash` function. + * + * @static + * @memberOf _ + * @category Util + * @returns {Function} Returns the `lodash` function. + * @example + * + * var lodash = _.noConflict(); + */ + function noConflict() { + if (root._ === this) { + root._ = oldDash; + } + return this; + } + + /** + * A no-operation function that returns `undefined` regardless of the + * arguments it receives. + * + * @static + * @memberOf _ + * @category Util + * @example + * + * var object = { 'user': 'fred' }; + * + * _.noop(object) === undefined; + * // => true + */ + function noop() { + // No operation performed. + } + + /** + * Creates a function that returns its nth argument. + * + * @static + * @memberOf _ + * @category Util + * @param {number} [n=0] The index of the argument to return. + * @returns {Function} Returns the new function. + * @example + * + * var func = _.nthArg(1); + * + * func('a', 'b', 'c'); + * // => 'b' + */ + function nthArg(n) { + n = toInteger(n); + return function() { + return arguments[n]; + }; + } + + /** + * Creates a function that invokes `iteratees` with the arguments provided + * to the created function and returns their results. + * + * @static + * @memberOf _ + * @category Util + * @param {...(Function|Function[])} iteratees The iteratees to invoke. + * @returns {Function} Returns the new function. + * @example + * + * var func = _.over(Math.max, Math.min); + * + * func(1, 2, 3, 4); + * // => [4, 1] + */ + var over = createOver(arrayMap); + + /** + * Creates a function that checks if **all** of the `predicates` return + * truthy when invoked with the arguments provided to the created function. + * + * @static + * @memberOf _ + * @category Util + * @param {...(Function|Function[])} predicates The predicates to check. + * @returns {Function} Returns the new function. + * @example + * + * var func = _.overEvery(Boolean, isFinite); + * + * func('1'); + * // => true + * + * func(null); + * // => false + * + * func(NaN); + * // => false + */ + var overEvery = createOver(arrayEvery); + + /** + * Creates a function that checks if **any** of the `predicates` return + * truthy when invoked with the arguments provided to the created function. + * + * @static + * @memberOf _ + * @category Util + * @param {...(Function|Function[])} predicates The predicates to check. + * @returns {Function} Returns the new function. + * @example + * + * var func = _.overSome(Boolean, isFinite); + * + * func('1'); + * // => true + * + * func(null); + * // => true + * + * func(NaN); + * // => false + */ + var overSome = createOver(arraySome); + + /** + * Creates a function that returns the value at `path` of a given object. + * + * @static + * @memberOf _ + * @category Util + * @param {Array|string} path The path of the property to get. + * @returns {Function} Returns the new function. + * @example + * + * var objects = [ + * { 'a': { 'b': { 'c': 2 } } }, + * { 'a': { 'b': { 'c': 1 } } } + * ]; + * + * _.map(objects, _.property('a.b.c')); + * // => [2, 1] + * + * _.map(_.sortBy(objects, _.property(['a', 'b', 'c'])), 'a.b.c'); + * // => [1, 2] + */ + function property(path) { + return isKey(path) ? baseProperty(path) : basePropertyDeep(path); + } + + /** + * The opposite of `_.property`; this method creates a function that returns + * the value at a given path of `object`. + * + * @static + * @memberOf _ + * @category Util + * @param {Object} object The object to query. + * @returns {Function} Returns the new function. + * @example + * + * var array = [0, 1, 2], + * object = { 'a': array, 'b': array, 'c': array }; + * + * _.map(['a[2]', 'c[0]'], _.propertyOf(object)); + * // => [2, 0] + * + * _.map([['a', '2'], ['c', '0']], _.propertyOf(object)); + * // => [2, 0] + */ + function propertyOf(object) { + return function(path) { + return object == null ? undefined : baseGet(object, path); + }; + } + + /** + * Creates an array of numbers (positive and/or negative) progressing from + * `start` up to, but not including, `end`. A step of `-1` is used if a negative + * `start` is specified without an `end` or `step`. If `end` is not specified + * it's set to `start` with `start` then set to `0`. + * + * **Note:** JavaScript follows the IEEE-754 standard for resolving + * floating-point values which can produce unexpected results. + * + * @static + * @memberOf _ + * @category Util + * @param {number} [start=0] The start of the range. + * @param {number} end The end of the range. + * @param {number} [step=1] The value to increment or decrement by. + * @returns {Array} Returns the new array of numbers. + * @example + * + * _.range(4); + * // => [0, 1, 2, 3] + * + * _.range(-4); + * // => [0, -1, -2, -3] + * + * _.range(1, 5); + * // => [1, 2, 3, 4] + * + * _.range(0, 20, 5); + * // => [0, 5, 10, 15] + * + * _.range(0, -4, -1); + * // => [0, -1, -2, -3] + * + * _.range(1, 4, 0); + * // => [1, 1, 1] + * + * _.range(0); + * // => [] + */ + var range = createRange(); + + /** + * This method is like `_.range` except that it populates values in + * descending order. + * + * @static + * @memberOf _ + * @category Util + * @param {number} [start=0] The start of the range. + * @param {number} end The end of the range. + * @param {number} [step=1] The value to increment or decrement by. + * @returns {Array} Returns the new array of numbers. + * @example + * + * _.rangeRight(4); + * // => [3, 2, 1, 0] + * + * _.rangeRight(-4); + * // => [-3, -2, -1, 0] + * + * _.rangeRight(1, 5); + * // => [4, 3, 2, 1] + * + * _.rangeRight(0, 20, 5); + * // => [15, 10, 5, 0] + * + * _.rangeRight(0, -4, -1); + * // => [-3, -2, -1, 0] + * + * _.rangeRight(1, 4, 0); + * // => [1, 1, 1] + * + * _.rangeRight(0); + * // => [] + */ + var rangeRight = createRange(true); + + /** + * Invokes the iteratee `n` times, returning an array of the results of + * each invocation. The iteratee is invoked with one argument; (index). + * + * @static + * @memberOf _ + * @category Util + * @param {number} n The number of times to invoke `iteratee`. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @returns {Array} Returns the array of results. + * @example + * + * _.times(3, String); + * // => ['0', '1', '2'] + * + * _.times(4, _.constant(true)); + * // => [true, true, true, true] + */ + function times(n, iteratee) { + n = toInteger(n); + if (n < 1 || n > MAX_SAFE_INTEGER) { + return []; + } + var index = MAX_ARRAY_LENGTH, + length = nativeMin(n, MAX_ARRAY_LENGTH); + + iteratee = baseCastFunction(iteratee); + n -= MAX_ARRAY_LENGTH; + + var result = baseTimes(length, iteratee); + while (++index < n) { + iteratee(index); + } + return result; + } + + /** + * Converts `value` to a property path array. + * + * @static + * @memberOf _ + * @category Util + * @param {*} value The value to convert. + * @returns {Array} Returns the new property path array. + * @example + * + * _.toPath('a.b.c'); + * // => ['a', 'b', 'c'] + * + * _.toPath('a[0].b.c'); + * // => ['a', '0', 'b', 'c'] + * + * var path = ['a', 'b', 'c'], + * newPath = _.toPath(path); + * + * console.log(newPath); + * // => ['a', 'b', 'c'] + * + * console.log(path === newPath); + * // => false + */ + function toPath(value) { + return isArray(value) ? arrayMap(value, String) : stringToPath(value); + } + + /** + * Generates a unique ID. If `prefix` is given the ID is appended to it. + * + * @static + * @memberOf _ + * @category Util + * @param {string} [prefix=''] The value to prefix the ID with. + * @returns {string} Returns the unique ID. + * @example + * + * _.uniqueId('contact_'); + * // => 'contact_104' + * + * _.uniqueId(); + * // => '105' + */ + function uniqueId(prefix) { + var id = ++idCounter; + return toString(prefix) + id; + } + + /*------------------------------------------------------------------------*/ + + /** + * Adds two numbers. + * + * @static + * @memberOf _ + * @category Math + * @param {number} augend The first number in an addition. + * @param {number} addend The second number in an addition. + * @returns {number} Returns the total. + * @example + * + * _.add(6, 4); + * // => 10 + */ + function add(augend, addend) { + var result; + if (augend === undefined && addend === undefined) { + return 0; + } + if (augend !== undefined) { + result = augend; + } + if (addend !== undefined) { + result = result === undefined ? addend : (result + addend); + } + return result; + } + + /** + * Computes `number` rounded up to `precision`. + * + * @static + * @memberOf _ + * @category Math + * @param {number} number The number to round up. + * @param {number} [precision=0] The precision to round up to. + * @returns {number} Returns the rounded up number. + * @example + * + * _.ceil(4.006); + * // => 5 + * + * _.ceil(6.004, 2); + * // => 6.01 + * + * _.ceil(6040, -2); + * // => 6100 + */ + var ceil = createRound('ceil'); + + /** + * Computes `number` rounded down to `precision`. + * + * @static + * @memberOf _ + * @category Math + * @param {number} number The number to round down. + * @param {number} [precision=0] The precision to round down to. + * @returns {number} Returns the rounded down number. + * @example + * + * _.floor(4.006); + * // => 4 + * + * _.floor(0.046, 2); + * // => 0.04 + * + * _.floor(4060, -2); + * // => 4000 + */ + var floor = createRound('floor'); + + /** + * Computes the maximum value of `array`. If `array` is empty or falsey + * `undefined` is returned. + * + * @static + * @memberOf _ + * @category Math + * @param {Array} array The array to iterate over. + * @returns {*} Returns the maximum value. + * @example + * + * _.max([4, 2, 8, 6]); + * // => 8 + * + * _.max([]); + * // => undefined + */ + function max(array) { + return (array && array.length) + ? baseExtremum(array, identity, gt) + : undefined; + } + + /** + * This method is like `_.max` except that it accepts `iteratee` which is + * invoked for each element in `array` to generate the criterion by which + * the value is ranked. The iteratee is invoked with one argument: (value). + * + * @static + * @memberOf _ + * @category Math + * @param {Array} array The array to iterate over. + * @param {Function|Object|string} [iteratee=_.identity] The iteratee invoked per element. + * @returns {*} Returns the maximum value. + * @example + * + * var objects = [{ 'n': 1 }, { 'n': 2 }]; + * + * _.maxBy(objects, function(o) { return o.n; }); + * // => { 'n': 2 } + * + * // The `_.property` iteratee shorthand. + * _.maxBy(objects, 'n'); + * // => { 'n': 2 } + */ + function maxBy(array, iteratee) { + return (array && array.length) + ? baseExtremum(array, getIteratee(iteratee), gt) + : undefined; + } + + /** + * Computes the mean of the values in `array`. + * + * @static + * @memberOf _ + * @category Math + * @param {Array} array The array to iterate over. + * @returns {number} Returns the mean. + * @example + * + * _.mean([4, 2, 8, 6]); + * // => 5 + */ + function mean(array) { + return sum(array) / (array ? array.length : 0); + } + + /** + * Computes the minimum value of `array`. If `array` is empty or falsey + * `undefined` is returned. + * + * @static + * @memberOf _ + * @category Math + * @param {Array} array The array to iterate over. + * @returns {*} Returns the minimum value. + * @example + * + * _.min([4, 2, 8, 6]); + * // => 2 + * + * _.min([]); + * // => undefined + */ + function min(array) { + return (array && array.length) + ? baseExtremum(array, identity, lt) + : undefined; + } + + /** + * This method is like `_.min` except that it accepts `iteratee` which is + * invoked for each element in `array` to generate the criterion by which + * the value is ranked. The iteratee is invoked with one argument: (value). + * + * @static + * @memberOf _ + * @category Math + * @param {Array} array The array to iterate over. + * @param {Function|Object|string} [iteratee=_.identity] The iteratee invoked per element. + * @returns {*} Returns the minimum value. + * @example + * + * var objects = [{ 'n': 1 }, { 'n': 2 }]; + * + * _.minBy(objects, function(o) { return o.n; }); + * // => { 'n': 1 } + * + * // The `_.property` iteratee shorthand. + * _.minBy(objects, 'n'); + * // => { 'n': 1 } + */ + function minBy(array, iteratee) { + return (array && array.length) + ? baseExtremum(array, getIteratee(iteratee), lt) + : undefined; + } + + /** + * Computes `number` rounded to `precision`. + * + * @static + * @memberOf _ + * @category Math + * @param {number} number The number to round. + * @param {number} [precision=0] The precision to round to. + * @returns {number} Returns the rounded number. + * @example + * + * _.round(4.006); + * // => 4 + * + * _.round(4.006, 2); + * // => 4.01 + * + * _.round(4060, -2); + * // => 4100 + */ + var round = createRound('round'); + + /** + * Subtract two numbers. + * + * @static + * @memberOf _ + * @category Math + * @param {number} minuend The first number in a subtraction. + * @param {number} subtrahend The second number in a subtraction. + * @returns {number} Returns the difference. + * @example + * + * _.subtract(6, 4); + * // => 2 + */ + function subtract(minuend, subtrahend) { + var result; + if (minuend === undefined && subtrahend === undefined) { + return 0; + } + if (minuend !== undefined) { + result = minuend; + } + if (subtrahend !== undefined) { + result = result === undefined ? subtrahend : (result - subtrahend); + } + return result; + } + + /** + * Computes the sum of the values in `array`. + * + * @static + * @memberOf _ + * @category Math + * @param {Array} array The array to iterate over. + * @returns {number} Returns the sum. + * @example + * + * _.sum([4, 2, 8, 6]); + * // => 20 + */ + function sum(array) { + return (array && array.length) + ? baseSum(array, identity) + : 0; + } + + /** + * This method is like `_.sum` except that it accepts `iteratee` which is + * invoked for each element in `array` to generate the value to be summed. + * The iteratee is invoked with one argument: (value). + * + * @static + * @memberOf _ + * @category Math + * @param {Array} array The array to iterate over. + * @param {Function|Object|string} [iteratee=_.identity] The iteratee invoked per element. + * @returns {number} Returns the sum. + * @example + * + * var objects = [{ 'n': 4 }, { 'n': 2 }, { 'n': 8 }, { 'n': 6 }]; + * + * _.sumBy(objects, function(o) { return o.n; }); + * // => 20 + * + * // The `_.property` iteratee shorthand. + * _.sumBy(objects, 'n'); + * // => 20 + */ + function sumBy(array, iteratee) { + return (array && array.length) + ? baseSum(array, getIteratee(iteratee)) + : 0; + } + + /*------------------------------------------------------------------------*/ + + // Ensure wrappers are instances of `baseLodash`. + lodash.prototype = baseLodash.prototype; + + LodashWrapper.prototype = baseCreate(baseLodash.prototype); + LodashWrapper.prototype.constructor = LodashWrapper; + + LazyWrapper.prototype = baseCreate(baseLodash.prototype); + LazyWrapper.prototype.constructor = LazyWrapper; + + // Avoid inheriting from `Object.prototype` when possible. + Hash.prototype = nativeCreate ? nativeCreate(null) : objectProto; + + // Add functions to the `MapCache`. + MapCache.prototype.clear = mapClear; + MapCache.prototype['delete'] = mapDelete; + MapCache.prototype.get = mapGet; + MapCache.prototype.has = mapHas; + MapCache.prototype.set = mapSet; + + // Add functions to the `SetCache`. + SetCache.prototype.push = cachePush; + + // Add functions to the `Stack` cache. + Stack.prototype.clear = stackClear; + Stack.prototype['delete'] = stackDelete; + Stack.prototype.get = stackGet; + Stack.prototype.has = stackHas; + Stack.prototype.set = stackSet; + + // Assign cache to `_.memoize`. + memoize.Cache = MapCache; + + // Add functions that return wrapped values when chaining. + lodash.after = after; + lodash.ary = ary; + lodash.assign = assign; + lodash.assignIn = assignIn; + lodash.assignInWith = assignInWith; + lodash.assignWith = assignWith; + lodash.at = at; + lodash.before = before; + lodash.bind = bind; + lodash.bindAll = bindAll; + lodash.bindKey = bindKey; + lodash.castArray = castArray; + lodash.chain = chain; + lodash.chunk = chunk; + lodash.compact = compact; + lodash.concat = concat; + lodash.cond = cond; + lodash.conforms = conforms; + lodash.constant = constant; + lodash.countBy = countBy; + lodash.create = create; + lodash.curry = curry; + lodash.curryRight = curryRight; + lodash.debounce = debounce; + lodash.defaults = defaults; + lodash.defaultsDeep = defaultsDeep; + lodash.defer = defer; + lodash.delay = delay; + lodash.difference = difference; + lodash.differenceBy = differenceBy; + lodash.differenceWith = differenceWith; + lodash.drop = drop; + lodash.dropRight = dropRight; + lodash.dropRightWhile = dropRightWhile; + lodash.dropWhile = dropWhile; + lodash.fill = fill; + lodash.filter = filter; + lodash.flatMap = flatMap; + lodash.flatten = flatten; + lodash.flattenDeep = flattenDeep; + lodash.flattenDepth = flattenDepth; + lodash.flip = flip; + lodash.flow = flow; + lodash.flowRight = flowRight; + lodash.fromPairs = fromPairs; + lodash.functions = functions; + lodash.functionsIn = functionsIn; + lodash.groupBy = groupBy; + lodash.initial = initial; + lodash.intersection = intersection; + lodash.intersectionBy = intersectionBy; + lodash.intersectionWith = intersectionWith; + lodash.invert = invert; + lodash.invertBy = invertBy; + lodash.invokeMap = invokeMap; + lodash.iteratee = iteratee; + lodash.keyBy = keyBy; + lodash.keys = keys; + lodash.keysIn = keysIn; + lodash.map = map; + lodash.mapKeys = mapKeys; + lodash.mapValues = mapValues; + lodash.matches = matches; + lodash.matchesProperty = matchesProperty; + lodash.memoize = memoize; + lodash.merge = merge; + lodash.mergeWith = mergeWith; + lodash.method = method; + lodash.methodOf = methodOf; + lodash.mixin = mixin; + lodash.negate = negate; + lodash.nthArg = nthArg; + lodash.omit = omit; + lodash.omitBy = omitBy; + lodash.once = once; + lodash.orderBy = orderBy; + lodash.over = over; + lodash.overArgs = overArgs; + lodash.overEvery = overEvery; + lodash.overSome = overSome; + lodash.partial = partial; + lodash.partialRight = partialRight; + lodash.partition = partition; + lodash.pick = pick; + lodash.pickBy = pickBy; + lodash.property = property; + lodash.propertyOf = propertyOf; + lodash.pull = pull; + lodash.pullAll = pullAll; + lodash.pullAllBy = pullAllBy; + lodash.pullAt = pullAt; + lodash.range = range; + lodash.rangeRight = rangeRight; + lodash.rearg = rearg; + lodash.reject = reject; + lodash.remove = remove; + lodash.rest = rest; + lodash.reverse = reverse; + lodash.sampleSize = sampleSize; + lodash.set = set; + lodash.setWith = setWith; + lodash.shuffle = shuffle; + lodash.slice = slice; + lodash.sortBy = sortBy; + lodash.sortedUniq = sortedUniq; + lodash.sortedUniqBy = sortedUniqBy; + lodash.split = split; + lodash.spread = spread; + lodash.tail = tail; + lodash.take = take; + lodash.takeRight = takeRight; + lodash.takeRightWhile = takeRightWhile; + lodash.takeWhile = takeWhile; + lodash.tap = tap; + lodash.throttle = throttle; + lodash.thru = thru; + lodash.toArray = toArray; + lodash.toPairs = toPairs; + lodash.toPairsIn = toPairsIn; + lodash.toPath = toPath; + lodash.toPlainObject = toPlainObject; + lodash.transform = transform; + lodash.unary = unary; + lodash.union = union; + lodash.unionBy = unionBy; + lodash.unionWith = unionWith; + lodash.uniq = uniq; + lodash.uniqBy = uniqBy; + lodash.uniqWith = uniqWith; + lodash.unset = unset; + lodash.unzip = unzip; + lodash.unzipWith = unzipWith; + lodash.values = values; + lodash.valuesIn = valuesIn; + lodash.without = without; + lodash.words = words; + lodash.wrap = wrap; + lodash.xor = xor; + lodash.xorBy = xorBy; + lodash.xorWith = xorWith; + lodash.zip = zip; + lodash.zipObject = zipObject; + lodash.zipObjectDeep = zipObjectDeep; + lodash.zipWith = zipWith; + + // Add aliases. + lodash.extend = assignIn; + lodash.extendWith = assignInWith; + + // Add functions to `lodash.prototype`. + mixin(lodash, lodash); + + /*------------------------------------------------------------------------*/ + + // Add functions that return unwrapped values when chaining. + lodash.add = add; + lodash.attempt = attempt; + lodash.camelCase = camelCase; + lodash.capitalize = capitalize; + lodash.ceil = ceil; + lodash.clamp = clamp; + lodash.clone = clone; + lodash.cloneDeep = cloneDeep; + lodash.cloneDeepWith = cloneDeepWith; + lodash.cloneWith = cloneWith; + lodash.deburr = deburr; + lodash.endsWith = endsWith; + lodash.eq = eq; + lodash.escape = escape; + lodash.escapeRegExp = escapeRegExp; + lodash.every = every; + lodash.find = find; + lodash.findIndex = findIndex; + lodash.findKey = findKey; + lodash.findLast = findLast; + lodash.findLastIndex = findLastIndex; + lodash.findLastKey = findLastKey; + lodash.floor = floor; + lodash.forEach = forEach; + lodash.forEachRight = forEachRight; + lodash.forIn = forIn; + lodash.forInRight = forInRight; + lodash.forOwn = forOwn; + lodash.forOwnRight = forOwnRight; + lodash.get = get; + lodash.gt = gt; + lodash.gte = gte; + lodash.has = has; + lodash.hasIn = hasIn; + lodash.head = head; + lodash.identity = identity; + lodash.includes = includes; + lodash.indexOf = indexOf; + lodash.inRange = inRange; + lodash.invoke = invoke; + lodash.isArguments = isArguments; + lodash.isArray = isArray; + lodash.isArrayBuffer = isArrayBuffer; + lodash.isArrayLike = isArrayLike; + lodash.isArrayLikeObject = isArrayLikeObject; + lodash.isBoolean = isBoolean; + lodash.isBuffer = isBuffer; + lodash.isDate = isDate; + lodash.isElement = isElement; + lodash.isEmpty = isEmpty; + lodash.isEqual = isEqual; + lodash.isEqualWith = isEqualWith; + lodash.isError = isError; + lodash.isFinite = isFinite; + lodash.isFunction = isFunction; + lodash.isInteger = isInteger; + lodash.isLength = isLength; + lodash.isMap = isMap; + lodash.isMatch = isMatch; + lodash.isMatchWith = isMatchWith; + lodash.isNaN = isNaN; + lodash.isNative = isNative; + lodash.isNil = isNil; + lodash.isNull = isNull; + lodash.isNumber = isNumber; + lodash.isObject = isObject; + lodash.isObjectLike = isObjectLike; + lodash.isPlainObject = isPlainObject; + lodash.isRegExp = isRegExp; + lodash.isSafeInteger = isSafeInteger; + lodash.isSet = isSet; + lodash.isString = isString; + lodash.isSymbol = isSymbol; + lodash.isTypedArray = isTypedArray; + lodash.isUndefined = isUndefined; + lodash.isWeakMap = isWeakMap; + lodash.isWeakSet = isWeakSet; + lodash.join = join; + lodash.kebabCase = kebabCase; + lodash.last = last; + lodash.lastIndexOf = lastIndexOf; + lodash.lowerCase = lowerCase; + lodash.lowerFirst = lowerFirst; + lodash.lt = lt; + lodash.lte = lte; + lodash.max = max; + lodash.maxBy = maxBy; + lodash.mean = mean; + lodash.min = min; + lodash.minBy = minBy; + lodash.noConflict = noConflict; + lodash.noop = noop; + lodash.now = now; + lodash.pad = pad; + lodash.padEnd = padEnd; + lodash.padStart = padStart; + lodash.parseInt = parseInt; + lodash.random = random; + lodash.reduce = reduce; + lodash.reduceRight = reduceRight; + lodash.repeat = repeat; + lodash.replace = replace; + lodash.result = result; + lodash.round = round; + lodash.runInContext = runInContext; + lodash.sample = sample; + lodash.size = size; + lodash.snakeCase = snakeCase; + lodash.some = some; + lodash.sortedIndex = sortedIndex; + lodash.sortedIndexBy = sortedIndexBy; + lodash.sortedIndexOf = sortedIndexOf; + lodash.sortedLastIndex = sortedLastIndex; + lodash.sortedLastIndexBy = sortedLastIndexBy; + lodash.sortedLastIndexOf = sortedLastIndexOf; + lodash.startCase = startCase; + lodash.startsWith = startsWith; + lodash.subtract = subtract; + lodash.sum = sum; + lodash.sumBy = sumBy; + lodash.template = template; + lodash.times = times; + lodash.toInteger = toInteger; + lodash.toLength = toLength; + lodash.toLower = toLower; + lodash.toNumber = toNumber; + lodash.toSafeInteger = toSafeInteger; + lodash.toString = toString; + lodash.toUpper = toUpper; + lodash.trim = trim; + lodash.trimEnd = trimEnd; + lodash.trimStart = trimStart; + lodash.truncate = truncate; + lodash.unescape = unescape; + lodash.uniqueId = uniqueId; + lodash.upperCase = upperCase; + lodash.upperFirst = upperFirst; + + // Add aliases. + lodash.each = forEach; + lodash.eachRight = forEachRight; + lodash.first = head; + + mixin(lodash, (function() { + var source = {}; + baseForOwn(lodash, function(func, methodName) { + if (!hasOwnProperty.call(lodash.prototype, methodName)) { + source[methodName] = func; + } + }); + return source; + }()), { 'chain': false }); + + /*------------------------------------------------------------------------*/ + + /** + * The semantic version number. + * + * @static + * @memberOf _ + * @type {string} + */ + lodash.VERSION = VERSION; + + // Assign default placeholders. + arrayEach(['bind', 'bindKey', 'curry', 'curryRight', 'partial', 'partialRight'], function(methodName) { + lodash[methodName].placeholder = lodash; + }); + + // Add `LazyWrapper` methods for `_.drop` and `_.take` variants. + arrayEach(['drop', 'take'], function(methodName, index) { + LazyWrapper.prototype[methodName] = function(n) { + var filtered = this.__filtered__; + if (filtered && !index) { + return new LazyWrapper(this); + } + n = n === undefined ? 1 : nativeMax(toInteger(n), 0); + + var result = this.clone(); + if (filtered) { + result.__takeCount__ = nativeMin(n, result.__takeCount__); + } else { + result.__views__.push({ + 'size': nativeMin(n, MAX_ARRAY_LENGTH), + 'type': methodName + (result.__dir__ < 0 ? 'Right' : '') + }); + } + return result; + }; + + LazyWrapper.prototype[methodName + 'Right'] = function(n) { + return this.reverse()[methodName](n).reverse(); + }; + }); + + // Add `LazyWrapper` methods that accept an `iteratee` value. + arrayEach(['filter', 'map', 'takeWhile'], function(methodName, index) { + var type = index + 1, + isFilter = type == LAZY_FILTER_FLAG || type == LAZY_WHILE_FLAG; + + LazyWrapper.prototype[methodName] = function(iteratee) { + var result = this.clone(); + result.__iteratees__.push({ + 'iteratee': getIteratee(iteratee, 3), + 'type': type + }); + result.__filtered__ = result.__filtered__ || isFilter; + return result; + }; + }); + + // Add `LazyWrapper` methods for `_.head` and `_.last`. + arrayEach(['head', 'last'], function(methodName, index) { + var takeName = 'take' + (index ? 'Right' : ''); + + LazyWrapper.prototype[methodName] = function() { + return this[takeName](1).value()[0]; + }; + }); + + // Add `LazyWrapper` methods for `_.initial` and `_.tail`. + arrayEach(['initial', 'tail'], function(methodName, index) { + var dropName = 'drop' + (index ? '' : 'Right'); + + LazyWrapper.prototype[methodName] = function() { + return this.__filtered__ ? new LazyWrapper(this) : this[dropName](1); + }; + }); + + LazyWrapper.prototype.compact = function() { + return this.filter(identity); + }; + + LazyWrapper.prototype.find = function(predicate) { + return this.filter(predicate).head(); + }; + + LazyWrapper.prototype.findLast = function(predicate) { + return this.reverse().find(predicate); + }; + + LazyWrapper.prototype.invokeMap = rest(function(path, args) { + if (typeof path == 'function') { + return new LazyWrapper(this); + } + return this.map(function(value) { + return baseInvoke(value, path, args); + }); + }); + + LazyWrapper.prototype.reject = function(predicate) { + predicate = getIteratee(predicate, 3); + return this.filter(function(value) { + return !predicate(value); + }); + }; + + LazyWrapper.prototype.slice = function(start, end) { + start = toInteger(start); + + var result = this; + if (result.__filtered__ && (start > 0 || end < 0)) { + return new LazyWrapper(result); + } + if (start < 0) { + result = result.takeRight(-start); + } else if (start) { + result = result.drop(start); + } + if (end !== undefined) { + end = toInteger(end); + result = end < 0 ? result.dropRight(-end) : result.take(end - start); + } + return result; + }; + + LazyWrapper.prototype.takeRightWhile = function(predicate) { + return this.reverse().takeWhile(predicate).reverse(); + }; + + LazyWrapper.prototype.toArray = function() { + return this.take(MAX_ARRAY_LENGTH); + }; + + // Add `LazyWrapper` methods to `lodash.prototype`. + baseForOwn(LazyWrapper.prototype, function(func, methodName) { + var checkIteratee = /^(?:filter|find|map|reject)|While$/.test(methodName), + isTaker = /^(?:head|last)$/.test(methodName), + lodashFunc = lodash[isTaker ? ('take' + (methodName == 'last' ? 'Right' : '')) : methodName], + retUnwrapped = isTaker || /^find/.test(methodName); + + if (!lodashFunc) { + return; + } + lodash.prototype[methodName] = function() { + var value = this.__wrapped__, + args = isTaker ? [1] : arguments, + isLazy = value instanceof LazyWrapper, + iteratee = args[0], + useLazy = isLazy || isArray(value); + + var interceptor = function(value) { + var result = lodashFunc.apply(lodash, arrayPush([value], args)); + return (isTaker && chainAll) ? result[0] : result; + }; + + if (useLazy && checkIteratee && typeof iteratee == 'function' && iteratee.length != 1) { + // Avoid lazy use if the iteratee has a "length" value other than `1`. + isLazy = useLazy = false; + } + var chainAll = this.__chain__, + isHybrid = !!this.__actions__.length, + isUnwrapped = retUnwrapped && !chainAll, + onlyLazy = isLazy && !isHybrid; + + if (!retUnwrapped && useLazy) { + value = onlyLazy ? value : new LazyWrapper(this); + var result = func.apply(value, args); + result.__actions__.push({ 'func': thru, 'args': [interceptor], 'thisArg': undefined }); + return new LodashWrapper(result, chainAll); + } + if (isUnwrapped && onlyLazy) { + return func.apply(this, args); + } + result = this.thru(interceptor); + return isUnwrapped ? (isTaker ? result.value()[0] : result.value()) : result; + }; + }); + + // Add `Array` and `String` methods to `lodash.prototype`. + arrayEach(['pop', 'push', 'shift', 'sort', 'splice', 'unshift'], function(methodName) { + var func = arrayProto[methodName], + chainName = /^(?:push|sort|unshift)$/.test(methodName) ? 'tap' : 'thru', + retUnwrapped = /^(?:pop|shift)$/.test(methodName); + + lodash.prototype[methodName] = function() { + var args = arguments; + if (retUnwrapped && !this.__chain__) { + return func.apply(this.value(), args); + } + return this[chainName](function(value) { + return func.apply(value, args); + }); + }; + }); + + // Map minified function names to their real names. + baseForOwn(LazyWrapper.prototype, function(func, methodName) { + var lodashFunc = lodash[methodName]; + if (lodashFunc) { + var key = (lodashFunc.name + ''), + names = realNames[key] || (realNames[key] = []); + + names.push({ 'name': methodName, 'func': lodashFunc }); + } + }); + + realNames[createHybridWrapper(undefined, BIND_KEY_FLAG).name] = [{ + 'name': 'wrapper', + 'func': undefined + }]; + + // Add functions to the lazy wrapper. + LazyWrapper.prototype.clone = lazyClone; + LazyWrapper.prototype.reverse = lazyReverse; + LazyWrapper.prototype.value = lazyValue; + + // Add chaining functions to the `lodash` wrapper. + lodash.prototype.at = wrapperAt; + lodash.prototype.chain = wrapperChain; + lodash.prototype.commit = wrapperCommit; + lodash.prototype.flatMap = wrapperFlatMap; + lodash.prototype.next = wrapperNext; + lodash.prototype.plant = wrapperPlant; + lodash.prototype.reverse = wrapperReverse; + lodash.prototype.toJSON = lodash.prototype.valueOf = lodash.prototype.value = wrapperValue; + + if (iteratorSymbol) { + lodash.prototype[iteratorSymbol] = wrapperToIterator; + } + return lodash; + } + + /*--------------------------------------------------------------------------*/ + + // Export lodash. + var _ = runInContext(); + + // Expose lodash on the free variable `window` or `self` when available. This + // prevents errors in cases where lodash is loaded by a script tag in the presence + // of an AMD loader. See http://requirejs.org/docs/errors.html#mismatch for more details. + (freeWindow || freeSelf || {})._ = _; + + // Some AMD build optimizers like r.js check for condition patterns like the following: + if (typeof define == 'function' && typeof define.amd == 'object' && define.amd) { + // Define as an anonymous module so, through path mapping, it can be + // referenced as the "underscore" module. + define(function() { + return _; + }); + } + // Check for `exports` after `define` in case a build optimizer adds an `exports` object. + else if (freeExports && freeModule) { + // Export for Node.js. + if (moduleExports) { + (freeModule.exports = _)._ = _; + } + // Export for CommonJS support. + freeExports._ = _; + } + else { + // Export to the global object. + root._ = _; + } +}.call(this)); |