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/** Used as references for various `Number` constants. */
var MAX_SAFE_INTEGER = 9007199254740991;
/** Used to detect unsigned integer values. */
var reIsUint = /^(?:0|[1-9]\d*)$/;
/**
* 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) {
var type = typeof value;
length = length == null ? MAX_SAFE_INTEGER : length;
return !!length &&
(type == 'number' ||
(type != 'symbol' && reIsUint.test(value))) &&
(value > -1 && value % 1 == 0 && value < length);
}
module.exports = isIndex;
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