lodash/isEmpty.js

define(['./isArguments', './isArray', './isArrayLike', './isFunction', './isString'], function(isArguments, isArray, isArrayLike, isFunction, isString) {

  /** Used for built-in method references. */
  var objectProto = Object.prototype;

  /** Used to check objects for own properties. */
  var hasOwnProperty = objectProto.hasOwnProperty;

  /**
   * Checks if `value` is empty. A value is considered empty unless it's an
   * `arguments` object, array, string, or jQuery-like collection with a length
   * greater than `0` or an object with own enumerable properties.
   *
   * @static
   * @memberOf _
   * @category Lang
   * @param {Array|Object|string} value The value to inspect.
   * @returns {boolean} Returns `true` if `value` is empty, else `false`.
   * @example
   *
   * _.isEmpty(null);
   * // => true
   *
   * _.isEmpty(true);
   * // => true
   *
   * _.isEmpty(1);
   * // => true
   *
   * _.isEmpty([1, 2, 3]);
   * // => false
   *
   * _.isEmpty({ 'a': 1 });
   * // => false
   */
  function isEmpty(value) {
    if (isArrayLike(value) &&
        (isArray(value) || isString(value) || isFunction(value.splice) || isArguments(value))) {
      return !value.length;
    }
    for (var key in value) {
      if (hasOwnProperty.call(value, key)) {
        return false;
      }
    }
    return true;
  }

  return isEmpty;
});