1
 2/**
 3 * HOP ref.
 4 */
 5
 6var has = Object.prototype.hasOwnProperty;
 7
 8/**
 9 * Return own keys in `obj`.
10 *
11 * @param {Object} obj
12 * @return {Array}
13 * @api public
14 */
15
16exports.keys = Object.keys || function(obj){
17  var keys = [];
18  for (var key in obj) {
19    if (has.call(obj, key)) {
20      keys.push(key);
21    }
22  }
23  return keys;
24};
25
26/**
27 * Return own values in `obj`.
28 *
29 * @param {Object} obj
30 * @return {Array}
31 * @api public
32 */
33
34exports.values = function(obj){
35  var vals = [];
36  for (var key in obj) {
37    if (has.call(obj, key)) {
38      vals.push(obj[key]);
39    }
40  }
41  return vals;
42};
43
44/**
45 * Merge `b` into `a`.
46 *
47 * @param {Object} a
48 * @param {Object} b
49 * @return {Object} a
50 * @api public
51 */
52
53exports.merge = function(a, b){
54  for (var key in b) {
55    if (has.call(b, key)) {
56      a[key] = b[key];
57    }
58  }
59  return a;
60};
61
62/**
63 * Return length of `obj`.
64 *
65 * @param {Object} obj
66 * @return {Number}
67 * @api public
68 */
69
70exports.length = function(obj){
71  return exports.keys(obj).length;
72};
73
74/**
75 * Check if `obj` is empty.
76 *
77 * @param {Object} obj
78 * @return {Boolean}
79 * @api public
80 */
81
82exports.isEmpty = function(obj){
83  return 0 == exports.length(obj);
84};