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/** Used to detect unsigned integer values. */
var reIsUint = /^\d+$/;
/**
* Used as the [maximum length](http://ecma-international.org/ecma-262/6.0/#sec-number.max_safe_integer)
* of an array-like value.
*/
var MAX_SAFE_INTEGER = 9007199254740991;
/**
* 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;
}
module.exports = isIndex;
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