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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;