1  'use strict';
 2  
 3  exports.repeat = function (str, num) {
 4    var result = '';
 5    for (var i = 0; i < num; i++) { result += str; }
 6    return result;
 7  };
 8  
 9  exports.arrayEqual = function (a, b) {
10    if (a.length !== b.length) { return false; }
11    for (var i = 0; i < a.length; i++) {
12      if (a[i] !== b[i]) { return false; }
13    }
14    return true;
15  };
16  
17  exports.trimChars = function (str, chars) {
18    var start = 0;
19    var end = str.length - 1;
20    while (chars.indexOf(str.charAt(start)) >= 0) { start++; }
21    while (chars.indexOf(str.charAt(end)) >= 0) { end--; }
22    return str.slice(start, end + 1);
23  };
24  
25  exports.capitalize = function (str) {
26    return str.charAt(0).toUpperCase() + str.slice(1);
27  };
28  
29  exports.arrayUnion = function () {
30    var result = [];
31    for (var i = 0, values = {}; i < arguments.length; i++) {
32      var arr = arguments[i];
33      for (var j = 0; j < arr.length; j++) {
34        if (!values[arr[j]]) {
35          values[arr[j]] = true;
36          result.push(arr[j]);
37        }
38      }
39    }
40    return result;
41  };
42  
43  function has(obj, key) {
44    return Object.prototype.hasOwnProperty.call(obj, key);
45  }
46  
47  exports.has = has;
48  
49  exports.extend = function (dest, src) {
50    for (var i in src) {
51      if (has(src, i)) { dest[i] = src[i]; }
52    }
53  };
54  
55  exports.trimEnd = function (str) {
56    return str.replace(/\s+$/g, '');
57  };