Function isIndex

src/helpers/set.js:612–621

* 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`.

(value, length)

 * @returns {boolean} Returns `true` if `value` is a valid index, else `false`.
 */
function isIndex(value, length) {
  length = length == null ? MAX_SAFE_INTEGER : length;
  return (
    !!length &&
    (typeof value == 'number' || reIsUint.test(value)) &&
    value > -1 &&
    value % 1 == 0 &&
    value < length
  );
}

/**
 * Checks if `value` is a property name and not a property path.