code: function isIndex$3(value, length) {
  	  length = length == null ? MAX_SAFE_INTEGER$3 : length;
  	  return !!length &&
  	    (typeof value == 'number' || reIsUint$3.test(value)) &&
  	    (value > -1 && value % 1 == 0 && value < length);
  	}
docs: 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`.