Total Complexity | 310 |
Complexity/F | 2.28 |
Lines of Code | 991 |
Function Count | 136 |
Duplicated Lines | 20 |
Ratio | 2.02 % |
Changes | 0 |
Duplicate code is one of the most pungent code smells. A rule that is often used is to re-structure code once it is duplicated in three or more places.
Common duplication problems, and corresponding solutions are:
Complex classes like docs/build/html/_static/underscore-1.3.1.js often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
1 | // Underscore.js 1.3.1 |
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9 | (function() { |
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10 | |||
11 | // Baseline setup |
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12 | // -------------- |
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13 | |||
14 | // Establish the root object, `window` in the browser, or `global` on the server. |
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15 | var root = this; |
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16 | |||
17 | // Save the previous value of the `_` variable. |
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18 | var previousUnderscore = root._; |
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19 | |||
20 | // Establish the object that gets returned to break out of a loop iteration. |
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21 | var breaker = {}; |
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22 | |||
23 | // Save bytes in the minified (but not gzipped) version: |
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24 | var ArrayProto = Array.prototype, ObjProto = Object.prototype, FuncProto = Function.prototype; |
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25 | |||
26 | // Create quick reference variables for speed access to core prototypes. |
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27 | var slice = ArrayProto.slice, |
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28 | unshift = ArrayProto.unshift, |
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29 | toString = ObjProto.toString, |
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30 | hasOwnProperty = ObjProto.hasOwnProperty; |
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31 | |||
32 | // All **ECMAScript 5** native function implementations that we hope to use |
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33 | // are declared here. |
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34 | var |
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35 | nativeForEach = ArrayProto.forEach, |
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36 | nativeMap = ArrayProto.map, |
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37 | nativeReduce = ArrayProto.reduce, |
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38 | nativeReduceRight = ArrayProto.reduceRight, |
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39 | nativeFilter = ArrayProto.filter, |
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40 | nativeEvery = ArrayProto.every, |
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41 | nativeSome = ArrayProto.some, |
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42 | nativeIndexOf = ArrayProto.indexOf, |
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43 | nativeLastIndexOf = ArrayProto.lastIndexOf, |
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44 | nativeIsArray = Array.isArray, |
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45 | nativeKeys = Object.keys, |
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46 | nativeBind = FuncProto.bind; |
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47 | |||
48 | // Create a safe reference to the Underscore object for use below. |
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49 | var _ = function(obj) { return new wrapper(obj); }; |
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50 | |||
51 | // Export the Underscore object for **Node.js**, with |
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52 | // backwards-compatibility for the old `require()` API. If we're in |
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53 | // the browser, add `_` as a global object via a string identifier, |
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54 | // for Closure Compiler "advanced" mode. |
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55 | if (typeof exports !== 'undefined') { |
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56 | if (typeof module !== 'undefined' && module.exports) { |
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57 | exports = module.exports = _; |
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58 | } |
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59 | exports._ = _; |
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60 | } else { |
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61 | root['_'] = _; |
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62 | } |
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63 | |||
64 | // Current version. |
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65 | _.VERSION = '1.3.1'; |
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66 | |||
67 | // Collection Functions |
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68 | // -------------------- |
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69 | |||
70 | // The cornerstone, an `each` implementation, aka `forEach`. |
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71 | // Handles objects with the built-in `forEach`, arrays, and raw objects. |
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72 | // Delegates to **ECMAScript 5**'s native `forEach` if available. |
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73 | var each = _.each = _.forEach = function(obj, iterator, context) { |
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74 | if (obj == null) return; |
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75 | if (nativeForEach && obj.forEach === nativeForEach) { |
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76 | obj.forEach(iterator, context); |
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77 | } else if (obj.length === +obj.length) { |
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78 | for (var i = 0, l = obj.length; i < l; i++) { |
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79 | if (i in obj && iterator.call(context, obj[i], i, obj) === breaker) return; |
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80 | } |
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81 | } else { |
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82 | for (var key in obj) { |
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83 | if (_.has(obj, key)) { |
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84 | if (iterator.call(context, obj[key], key, obj) === breaker) return; |
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85 | } |
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86 | } |
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87 | } |
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88 | }; |
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89 | |||
90 | // Return the results of applying the iterator to each element. |
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91 | // Delegates to **ECMAScript 5**'s native `map` if available. |
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92 | _.map = _.collect = function(obj, iterator, context) { |
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93 | var results = []; |
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94 | if (obj == null) return results; |
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95 | if (nativeMap && obj.map === nativeMap) return obj.map(iterator, context); |
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96 | each(obj, function(value, index, list) { |
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97 | results[results.length] = iterator.call(context, value, index, list); |
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98 | }); |
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99 | if (obj.length === +obj.length) results.length = obj.length; |
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100 | return results; |
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101 | }; |
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102 | |||
103 | // **Reduce** builds up a single result from a list of values, aka `inject`, |
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104 | // or `foldl`. Delegates to **ECMAScript 5**'s native `reduce` if available. |
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105 | _.reduce = _.foldl = _.inject = function(obj, iterator, memo, context) { |
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106 | var initial = arguments.length > 2; |
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107 | if (obj == null) obj = []; |
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108 | if (nativeReduce && obj.reduce === nativeReduce) { |
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109 | if (context) iterator = _.bind(iterator, context); |
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110 | return initial ? obj.reduce(iterator, memo) : obj.reduce(iterator); |
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111 | } |
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112 | each(obj, function(value, index, list) { |
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113 | if (!initial) { |
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114 | memo = value; |
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115 | initial = true; |
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116 | } else { |
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117 | memo = iterator.call(context, memo, value, index, list); |
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118 | } |
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119 | }); |
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120 | if (!initial) throw new TypeError('Reduce of empty array with no initial value'); |
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121 | return memo; |
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122 | }; |
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123 | |||
124 | // The right-associative version of reduce, also known as `foldr`. |
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125 | // Delegates to **ECMAScript 5**'s native `reduceRight` if available. |
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126 | _.reduceRight = _.foldr = function(obj, iterator, memo, context) { |
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127 | var initial = arguments.length > 2; |
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128 | if (obj == null) obj = []; |
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129 | if (nativeReduceRight && obj.reduceRight === nativeReduceRight) { |
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130 | if (context) iterator = _.bind(iterator, context); |
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131 | return initial ? obj.reduceRight(iterator, memo) : obj.reduceRight(iterator); |
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132 | } |
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133 | var reversed = _.toArray(obj).reverse(); |
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134 | if (context && !initial) iterator = _.bind(iterator, context); |
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135 | return initial ? _.reduce(reversed, iterator, memo, context) : _.reduce(reversed, iterator); |
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136 | }; |
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137 | |||
138 | // Return the first value which passes a truth test. Aliased as `detect`. |
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139 | _.find = _.detect = function(obj, iterator, context) { |
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140 | var result; |
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141 | any(obj, function(value, index, list) { |
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142 | if (iterator.call(context, value, index, list)) { |
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143 | result = value; |
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144 | return true; |
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145 | } |
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146 | }); |
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147 | return result; |
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148 | }; |
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149 | |||
150 | // Return all the elements that pass a truth test. |
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151 | // Delegates to **ECMAScript 5**'s native `filter` if available. |
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152 | // Aliased as `select`. |
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153 | _.filter = _.select = function(obj, iterator, context) { |
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154 | var results = []; |
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155 | if (obj == null) return results; |
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156 | if (nativeFilter && obj.filter === nativeFilter) return obj.filter(iterator, context); |
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157 | each(obj, function(value, index, list) { |
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158 | if (iterator.call(context, value, index, list)) results[results.length] = value; |
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159 | }); |
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160 | return results; |
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161 | }; |
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162 | |||
163 | // Return all the elements for which a truth test fails. |
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164 | _.reject = function(obj, iterator, context) { |
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165 | var results = []; |
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166 | if (obj == null) return results; |
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167 | each(obj, function(value, index, list) { |
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168 | if (!iterator.call(context, value, index, list)) results[results.length] = value; |
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169 | }); |
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170 | return results; |
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171 | }; |
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172 | |||
173 | // Determine whether all of the elements match a truth test. |
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174 | // Delegates to **ECMAScript 5**'s native `every` if available. |
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175 | // Aliased as `all`. |
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176 | _.every = _.all = function(obj, iterator, context) { |
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177 | var result = true; |
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178 | if (obj == null) return result; |
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179 | if (nativeEvery && obj.every === nativeEvery) return obj.every(iterator, context); |
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180 | each(obj, function(value, index, list) { |
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181 | if (!(result = result && iterator.call(context, value, index, list))) return breaker; |
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182 | }); |
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183 | return result; |
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184 | }; |
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185 | |||
186 | // Determine if at least one element in the object matches a truth test. |
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187 | // Delegates to **ECMAScript 5**'s native `some` if available. |
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188 | // Aliased as `any`. |
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189 | var any = _.some = _.any = function(obj, iterator, context) { |
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190 | iterator || (iterator = _.identity); |
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191 | var result = false; |
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192 | if (obj == null) return result; |
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193 | if (nativeSome && obj.some === nativeSome) return obj.some(iterator, context); |
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194 | each(obj, function(value, index, list) { |
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195 | if (result || (result = iterator.call(context, value, index, list))) return breaker; |
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196 | }); |
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197 | return !!result; |
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198 | }; |
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199 | |||
200 | // Determine if a given value is included in the array or object using `===`. |
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201 | // Aliased as `contains`. |
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202 | _.include = _.contains = function(obj, target) { |
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203 | var found = false; |
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204 | if (obj == null) return found; |
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205 | if (nativeIndexOf && obj.indexOf === nativeIndexOf) return obj.indexOf(target) != -1; |
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206 | found = any(obj, function(value) { |
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207 | return value === target; |
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208 | }); |
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209 | return found; |
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210 | }; |
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211 | |||
212 | // Invoke a method (with arguments) on every item in a collection. |
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213 | _.invoke = function(obj, method) { |
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214 | var args = slice.call(arguments, 2); |
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215 | return _.map(obj, function(value) { |
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216 | return (_.isFunction(method) ? method || value : value[method]).apply(value, args); |
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217 | }); |
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218 | }; |
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219 | |||
220 | // Convenience version of a common use case of `map`: fetching a property. |
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221 | _.pluck = function(obj, key) { |
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222 | return _.map(obj, function(value){ return value[key]; }); |
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223 | }; |
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224 | |||
225 | // Return the maximum element or (element-based computation). |
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226 | View Code Duplication | _.max = function(obj, iterator, context) { |
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227 | if (!iterator && _.isArray(obj)) return Math.max.apply(Math, obj); |
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228 | if (!iterator && _.isEmpty(obj)) return -Infinity; |
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229 | var result = {computed : -Infinity}; |
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230 | each(obj, function(value, index, list) { |
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231 | var computed = iterator ? iterator.call(context, value, index, list) : value; |
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232 | computed >= result.computed && (result = {value : value, computed : computed}); |
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233 | }); |
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234 | return result.value; |
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235 | }; |
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236 | |||
237 | // Return the minimum element (or element-based computation). |
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238 | View Code Duplication | _.min = function(obj, iterator, context) { |
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239 | if (!iterator && _.isArray(obj)) return Math.min.apply(Math, obj); |
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240 | if (!iterator && _.isEmpty(obj)) return Infinity; |
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241 | var result = {computed : Infinity}; |
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242 | each(obj, function(value, index, list) { |
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243 | var computed = iterator ? iterator.call(context, value, index, list) : value; |
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244 | computed < result.computed && (result = {value : value, computed : computed}); |
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245 | }); |
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246 | return result.value; |
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247 | }; |
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248 | |||
249 | // Shuffle an array. |
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250 | _.shuffle = function(obj) { |
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251 | var shuffled = [], rand; |
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252 | each(obj, function(value, index, list) { |
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253 | if (index == 0) { |
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254 | shuffled[0] = value; |
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255 | } else { |
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256 | rand = Math.floor(Math.random() * (index + 1)); |
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257 | shuffled[index] = shuffled[rand]; |
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258 | shuffled[rand] = value; |
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259 | } |
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260 | }); |
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261 | return shuffled; |
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262 | }; |
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263 | |||
264 | // Sort the object's values by a criterion produced by an iterator. |
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265 | _.sortBy = function(obj, iterator, context) { |
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266 | return _.pluck(_.map(obj, function(value, index, list) { |
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267 | return { |
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268 | value : value, |
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269 | criteria : iterator.call(context, value, index, list) |
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270 | }; |
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271 | }).sort(function(left, right) { |
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272 | var a = left.criteria, b = right.criteria; |
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273 | return a < b ? -1 : a > b ? 1 : 0; |
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274 | }), 'value'); |
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275 | }; |
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276 | |||
277 | // Groups the object's values by a criterion. Pass either a string attribute |
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278 | // to group by, or a function that returns the criterion. |
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279 | _.groupBy = function(obj, val) { |
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280 | var result = {}; |
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281 | var iterator = _.isFunction(val) ? val : function(obj) { return obj[val]; }; |
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282 | each(obj, function(value, index) { |
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283 | var key = iterator(value, index); |
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284 | (result[key] || (result[key] = [])).push(value); |
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285 | }); |
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286 | return result; |
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287 | }; |
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288 | |||
289 | // Use a comparator function to figure out at what index an object should |
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290 | // be inserted so as to maintain order. Uses binary search. |
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291 | _.sortedIndex = function(array, obj, iterator) { |
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292 | iterator || (iterator = _.identity); |
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293 | var low = 0, high = array.length; |
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294 | while (low < high) { |
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295 | var mid = (low + high) >> 1; |
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296 | iterator(array[mid]) < iterator(obj) ? low = mid + 1 : high = mid; |
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297 | } |
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298 | return low; |
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299 | }; |
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300 | |||
301 | // Safely convert anything iterable into a real, live array. |
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302 | _.toArray = function(iterable) { |
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303 | if (!iterable) return []; |
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304 | if (iterable.toArray) return iterable.toArray(); |
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305 | if (_.isArray(iterable)) return slice.call(iterable); |
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306 | if (_.isArguments(iterable)) return slice.call(iterable); |
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307 | return _.values(iterable); |
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308 | }; |
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309 | |||
310 | // Return the number of elements in an object. |
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311 | _.size = function(obj) { |
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312 | return _.toArray(obj).length; |
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313 | }; |
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314 | |||
315 | // Array Functions |
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316 | // --------------- |
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317 | |||
318 | // Get the first element of an array. Passing **n** will return the first N |
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319 | // values in the array. Aliased as `head`. The **guard** check allows it to work |
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320 | // with `_.map`. |
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321 | _.first = _.head = function(array, n, guard) { |
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322 | return (n != null) && !guard ? slice.call(array, 0, n) : array[0]; |
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323 | }; |
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324 | |||
325 | // Returns everything but the last entry of the array. Especcialy useful on |
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326 | // the arguments object. Passing **n** will return all the values in |
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327 | // the array, excluding the last N. The **guard** check allows it to work with |
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328 | // `_.map`. |
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329 | _.initial = function(array, n, guard) { |
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330 | return slice.call(array, 0, array.length - ((n == null) || guard ? 1 : n)); |
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331 | }; |
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332 | |||
333 | // Get the last element of an array. Passing **n** will return the last N |
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334 | // values in the array. The **guard** check allows it to work with `_.map`. |
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335 | _.last = function(array, n, guard) { |
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336 | if ((n != null) && !guard) { |
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337 | return slice.call(array, Math.max(array.length - n, 0)); |
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338 | } else { |
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339 | return array[array.length - 1]; |
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340 | } |
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341 | }; |
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342 | |||
343 | // Returns everything but the first entry of the array. Aliased as `tail`. |
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344 | // Especially useful on the arguments object. Passing an **index** will return |
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345 | // the rest of the values in the array from that index onward. The **guard** |
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346 | // check allows it to work with `_.map`. |
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347 | _.rest = _.tail = function(array, index, guard) { |
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348 | return slice.call(array, (index == null) || guard ? 1 : index); |
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349 | }; |
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350 | |||
351 | // Trim out all falsy values from an array. |
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352 | _.compact = function(array) { |
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353 | return _.filter(array, function(value){ return !!value; }); |
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354 | }; |
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355 | |||
356 | // Return a completely flattened version of an array. |
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357 | _.flatten = function(array, shallow) { |
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358 | return _.reduce(array, function(memo, value) { |
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359 | if (_.isArray(value)) return memo.concat(shallow ? value : _.flatten(value)); |
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360 | memo[memo.length] = value; |
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361 | return memo; |
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362 | }, []); |
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363 | }; |
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364 | |||
365 | // Return a version of the array that does not contain the specified value(s). |
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366 | _.without = function(array) { |
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367 | return _.difference(array, slice.call(arguments, 1)); |
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368 | }; |
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369 | |||
370 | // Produce a duplicate-free version of the array. If the array has already |
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371 | // been sorted, you have the option of using a faster algorithm. |
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372 | // Aliased as `unique`. |
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373 | _.uniq = _.unique = function(array, isSorted, iterator) { |
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374 | var initial = iterator ? _.map(array, iterator) : array; |
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375 | var result = []; |
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376 | _.reduce(initial, function(memo, el, i) { |
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377 | if (0 == i || (isSorted === true ? _.last(memo) != el : !_.include(memo, el))) { |
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378 | memo[memo.length] = el; |
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379 | result[result.length] = array[i]; |
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380 | } |
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381 | return memo; |
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382 | }, []); |
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383 | return result; |
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384 | }; |
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385 | |||
386 | // Produce an array that contains the union: each distinct element from all of |
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387 | // the passed-in arrays. |
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388 | _.union = function() { |
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389 | return _.uniq(_.flatten(arguments, true)); |
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390 | }; |
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391 | |||
392 | // Produce an array that contains every item shared between all the |
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393 | // passed-in arrays. (Aliased as "intersect" for back-compat.) |
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394 | _.intersection = _.intersect = function(array) { |
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395 | var rest = slice.call(arguments, 1); |
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396 | return _.filter(_.uniq(array), function(item) { |
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397 | return _.every(rest, function(other) { |
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398 | return _.indexOf(other, item) >= 0; |
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399 | }); |
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400 | }); |
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401 | }; |
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402 | |||
403 | // Take the difference between one array and a number of other arrays. |
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404 | // Only the elements present in just the first array will remain. |
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405 | _.difference = function(array) { |
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406 | var rest = _.flatten(slice.call(arguments, 1)); |
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407 | return _.filter(array, function(value){ return !_.include(rest, value); }); |
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408 | }; |
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409 | |||
410 | // Zip together multiple lists into a single array -- elements that share |
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411 | // an index go together. |
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412 | _.zip = function() { |
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413 | var args = slice.call(arguments); |
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414 | var length = _.max(_.pluck(args, 'length')); |
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415 | var results = new Array(length); |
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416 | for (var i = 0; i < length; i++) results[i] = _.pluck(args, "" + i); |
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417 | return results; |
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418 | }; |
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419 | |||
420 | // If the browser doesn't supply us with indexOf (I'm looking at you, **MSIE**), |
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421 | // we need this function. Return the position of the first occurrence of an |
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422 | // item in an array, or -1 if the item is not included in the array. |
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423 | // Delegates to **ECMAScript 5**'s native `indexOf` if available. |
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424 | // If the array is large and already in sort order, pass `true` |
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425 | // for **isSorted** to use binary search. |
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426 | _.indexOf = function(array, item, isSorted) { |
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427 | if (array == null) return -1; |
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428 | var i, l; |
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429 | if (isSorted) { |
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430 | i = _.sortedIndex(array, item); |
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431 | return array[i] === item ? i : -1; |
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432 | } |
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433 | if (nativeIndexOf && array.indexOf === nativeIndexOf) return array.indexOf(item); |
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434 | for (i = 0, l = array.length; i < l; i++) if (i in array && array[i] === item) return i; |
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435 | return -1; |
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436 | }; |
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437 | |||
438 | // Delegates to **ECMAScript 5**'s native `lastIndexOf` if available. |
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439 | _.lastIndexOf = function(array, item) { |
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440 | if (array == null) return -1; |
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441 | if (nativeLastIndexOf && array.lastIndexOf === nativeLastIndexOf) return array.lastIndexOf(item); |
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442 | var i = array.length; |
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443 | while (i--) if (i in array && array[i] === item) return i; |
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444 | return -1; |
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445 | }; |
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446 | |||
447 | // Generate an integer Array containing an arithmetic progression. A port of |
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448 | // the native Python `range()` function. See |
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449 | // [the Python documentation](http://docs.python.org/library/functions.html#range). |
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450 | _.range = function(start, stop, step) { |
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451 | if (arguments.length <= 1) { |
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452 | stop = start || 0; |
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453 | start = 0; |
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454 | } |
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455 | step = arguments[2] || 1; |
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456 | |||
457 | var len = Math.max(Math.ceil((stop - start) / step), 0); |
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458 | var idx = 0; |
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459 | var range = new Array(len); |
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460 | |||
461 | while(idx < len) { |
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462 | range[idx++] = start; |
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463 | start += step; |
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464 | } |
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465 | |||
466 | return range; |
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467 | }; |
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468 | |||
469 | // Function (ahem) Functions |
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470 | // ------------------ |
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471 | |||
472 | // Reusable constructor function for prototype setting. |
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473 | var ctor = function(){}; |
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474 | |||
475 | // Create a function bound to a given object (assigning `this`, and arguments, |
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476 | // optionally). Binding with arguments is also known as `curry`. |
||
477 | // Delegates to **ECMAScript 5**'s native `Function.bind` if available. |
||
478 | // We check for `func.bind` first, to fail fast when `func` is undefined. |
||
479 | _.bind = function bind(func, context) { |
||
480 | var bound, args; |
||
481 | if (func.bind === nativeBind && nativeBind) return nativeBind.apply(func, slice.call(arguments, 1)); |
||
482 | if (!_.isFunction(func)) throw new TypeError; |
||
483 | args = slice.call(arguments, 2); |
||
484 | return bound = function() { |
||
485 | if (!(this instanceof bound)) return func.apply(context, args.concat(slice.call(arguments))); |
||
486 | ctor.prototype = func.prototype; |
||
487 | var self = new ctor; |
||
488 | var result = func.apply(self, args.concat(slice.call(arguments))); |
||
489 | if (Object(result) === result) return result; |
||
490 | return self; |
||
491 | }; |
||
492 | }; |
||
493 | |||
494 | // Bind all of an object's methods to that object. Useful for ensuring that |
||
495 | // all callbacks defined on an object belong to it. |
||
496 | _.bindAll = function(obj) { |
||
497 | var funcs = slice.call(arguments, 1); |
||
498 | if (funcs.length == 0) funcs = _.functions(obj); |
||
499 | each(funcs, function(f) { obj[f] = _.bind(obj[f], obj); }); |
||
500 | return obj; |
||
501 | }; |
||
502 | |||
503 | // Memoize an expensive function by storing its results. |
||
504 | _.memoize = function(func, hasher) { |
||
505 | var memo = {}; |
||
506 | hasher || (hasher = _.identity); |
||
507 | return function() { |
||
508 | var key = hasher.apply(this, arguments); |
||
509 | return _.has(memo, key) ? memo[key] : (memo[key] = func.apply(this, arguments)); |
||
510 | }; |
||
511 | }; |
||
512 | |||
513 | // Delays a function for the given number of milliseconds, and then calls |
||
514 | // it with the arguments supplied. |
||
515 | _.delay = function(func, wait) { |
||
516 | var args = slice.call(arguments, 2); |
||
517 | return setTimeout(function(){ return func.apply(func, args); }, wait); |
||
518 | }; |
||
519 | |||
520 | // Defers a function, scheduling it to run after the current call stack has |
||
521 | // cleared. |
||
522 | _.defer = function(func) { |
||
523 | return _.delay.apply(_, [func, 1].concat(slice.call(arguments, 1))); |
||
524 | }; |
||
525 | |||
526 | // Returns a function, that, when invoked, will only be triggered at most once |
||
527 | // during a given window of time. |
||
528 | _.throttle = function(func, wait) { |
||
529 | var context, args, timeout, throttling, more; |
||
530 | var whenDone = _.debounce(function(){ more = throttling = false; }, wait); |
||
531 | return function() { |
||
532 | context = this; args = arguments; |
||
533 | var later = function() { |
||
534 | timeout = null; |
||
535 | if (more) func.apply(context, args); |
||
536 | whenDone(); |
||
537 | }; |
||
538 | if (!timeout) timeout = setTimeout(later, wait); |
||
539 | if (throttling) { |
||
540 | more = true; |
||
541 | } else { |
||
542 | func.apply(context, args); |
||
543 | } |
||
544 | whenDone(); |
||
545 | throttling = true; |
||
546 | }; |
||
547 | }; |
||
548 | |||
549 | // Returns a function, that, as long as it continues to be invoked, will not |
||
550 | // be triggered. The function will be called after it stops being called for |
||
551 | // N milliseconds. |
||
552 | _.debounce = function(func, wait) { |
||
553 | var timeout; |
||
554 | return function() { |
||
555 | var context = this, args = arguments; |
||
556 | var later = function() { |
||
557 | timeout = null; |
||
558 | func.apply(context, args); |
||
559 | }; |
||
560 | clearTimeout(timeout); |
||
561 | timeout = setTimeout(later, wait); |
||
562 | }; |
||
563 | }; |
||
564 | |||
565 | // Returns a function that will be executed at most one time, no matter how |
||
566 | // often you call it. Useful for lazy initialization. |
||
567 | _.once = function(func) { |
||
568 | var ran = false, memo; |
||
569 | return function() { |
||
570 | if (ran) return memo; |
||
571 | ran = true; |
||
572 | return memo = func.apply(this, arguments); |
||
573 | }; |
||
574 | }; |
||
575 | |||
576 | // Returns the first function passed as an argument to the second, |
||
577 | // allowing you to adjust arguments, run code before and after, and |
||
578 | // conditionally execute the original function. |
||
579 | _.wrap = function(func, wrapper) { |
||
580 | return function() { |
||
581 | var args = [func].concat(slice.call(arguments, 0)); |
||
582 | return wrapper.apply(this, args); |
||
583 | }; |
||
584 | }; |
||
585 | |||
586 | // Returns a function that is the composition of a list of functions, each |
||
587 | // consuming the return value of the function that follows. |
||
588 | _.compose = function() { |
||
589 | var funcs = arguments; |
||
590 | return function() { |
||
591 | var args = arguments; |
||
592 | for (var i = funcs.length - 1; i >= 0; i--) { |
||
593 | args = [funcs[i].apply(this, args)]; |
||
594 | } |
||
595 | return args[0]; |
||
596 | }; |
||
597 | }; |
||
598 | |||
599 | // Returns a function that will only be executed after being called N times. |
||
600 | _.after = function(times, func) { |
||
601 | if (times <= 0) return func(); |
||
602 | return function() { |
||
603 | if (--times < 1) { return func.apply(this, arguments); } |
||
604 | }; |
||
605 | }; |
||
606 | |||
607 | // Object Functions |
||
608 | // ---------------- |
||
609 | |||
610 | // Retrieve the names of an object's properties. |
||
611 | // Delegates to **ECMAScript 5**'s native `Object.keys` |
||
612 | _.keys = nativeKeys || function(obj) { |
||
613 | if (obj !== Object(obj)) throw new TypeError('Invalid object'); |
||
614 | var keys = []; |
||
615 | for (var key in obj) if (_.has(obj, key)) keys[keys.length] = key; |
||
616 | return keys; |
||
617 | }; |
||
618 | |||
619 | // Retrieve the values of an object's properties. |
||
620 | _.values = function(obj) { |
||
621 | return _.map(obj, _.identity); |
||
622 | }; |
||
623 | |||
624 | // Return a sorted list of the function names available on the object. |
||
625 | // Aliased as `methods` |
||
626 | _.functions = _.methods = function(obj) { |
||
627 | var names = []; |
||
628 | for (var key in obj) { |
||
629 | if (_.isFunction(obj[key])) names.push(key); |
||
630 | } |
||
631 | return names.sort(); |
||
632 | }; |
||
633 | |||
634 | // Extend a given object with all the properties in passed-in object(s). |
||
635 | _.extend = function(obj) { |
||
636 | each(slice.call(arguments, 1), function(source) { |
||
637 | for (var prop in source) { |
||
638 | obj[prop] = source[prop]; |
||
639 | } |
||
640 | }); |
||
641 | return obj; |
||
642 | }; |
||
643 | |||
644 | // Fill in a given object with default properties. |
||
645 | _.defaults = function(obj) { |
||
646 | each(slice.call(arguments, 1), function(source) { |
||
647 | for (var prop in source) { |
||
648 | if (obj[prop] == null) obj[prop] = source[prop]; |
||
649 | } |
||
650 | }); |
||
651 | return obj; |
||
652 | }; |
||
653 | |||
654 | // Create a (shallow-cloned) duplicate of an object. |
||
655 | _.clone = function(obj) { |
||
656 | if (!_.isObject(obj)) return obj; |
||
657 | return _.isArray(obj) ? obj.slice() : _.extend({}, obj); |
||
658 | }; |
||
659 | |||
660 | // Invokes interceptor with the obj, and then returns obj. |
||
661 | // The primary purpose of this method is to "tap into" a method chain, in |
||
662 | // order to perform operations on intermediate results within the chain. |
||
663 | _.tap = function(obj, interceptor) { |
||
664 | interceptor(obj); |
||
665 | return obj; |
||
666 | }; |
||
667 | |||
668 | // Internal recursive comparison function. |
||
669 | function eq(a, b, stack) { |
||
670 | // Identical objects are equal. `0 === -0`, but they aren't identical. |
||
671 | // See the Harmony `egal` proposal: http://wiki.ecmascript.org/doku.php?id=harmony:egal. |
||
672 | if (a === b) return a !== 0 || 1 / a == 1 / b; |
||
673 | // A strict comparison is necessary because `null == undefined`. |
||
674 | if (a == null || b == null) return a === b; |
||
675 | // Unwrap any wrapped objects. |
||
676 | if (a._chain) a = a._wrapped; |
||
677 | if (b._chain) b = b._wrapped; |
||
678 | // Invoke a custom `isEqual` method if one is provided. |
||
679 | if (a.isEqual && _.isFunction(a.isEqual)) return a.isEqual(b); |
||
680 | if (b.isEqual && _.isFunction(b.isEqual)) return b.isEqual(a); |
||
681 | // Compare `[[Class]]` names. |
||
682 | var className = toString.call(a); |
||
683 | if (className != toString.call(b)) return false; |
||
684 | switch (className) { |
||
685 | // Strings, numbers, dates, and booleans are compared by value. |
||
686 | case '[object String]': |
||
687 | // Primitives and their corresponding object wrappers are equivalent; thus, `"5"` is |
||
688 | // equivalent to `new String("5")`. |
||
689 | return a == String(b); |
||
690 | case '[object Number]': |
||
691 | // `NaN`s are equivalent, but non-reflexive. An `egal` comparison is performed for |
||
692 | // other numeric values. |
||
693 | return a != +a ? b != +b : (a == 0 ? 1 / a == 1 / b : a == +b); |
||
694 | case '[object Date]': |
||
695 | case '[object Boolean]': |
||
696 | // Coerce dates and booleans to numeric primitive values. Dates are compared by their |
||
697 | // millisecond representations. Note that invalid dates with millisecond representations |
||
698 | // of `NaN` are not equivalent. |
||
699 | return +a == +b; |
||
700 | // RegExps are compared by their source patterns and flags. |
||
701 | case '[object RegExp]': |
||
702 | return a.source == b.source && |
||
703 | a.global == b.global && |
||
704 | a.multiline == b.multiline && |
||
705 | a.ignoreCase == b.ignoreCase; |
||
706 | } |
||
707 | if (typeof a != 'object' || typeof b != 'object') return false; |
||
708 | // Assume equality for cyclic structures. The algorithm for detecting cyclic |
||
709 | // structures is adapted from ES 5.1 section 15.12.3, abstract operation `JO`. |
||
710 | var length = stack.length; |
||
711 | while (length--) { |
||
712 | // Linear search. Performance is inversely proportional to the number of |
||
713 | // unique nested structures. |
||
714 | if (stack[length] == a) return true; |
||
715 | } |
||
716 | // Add the first object to the stack of traversed objects. |
||
717 | stack.push(a); |
||
718 | var size = 0, result = true; |
||
719 | // Recursively compare objects and arrays. |
||
720 | if (className == '[object Array]') { |
||
721 | // Compare array lengths to determine if a deep comparison is necessary. |
||
722 | size = a.length; |
||
723 | result = size == b.length; |
||
724 | if (result) { |
||
725 | // Deep compare the contents, ignoring non-numeric properties. |
||
726 | while (size--) { |
||
727 | // Ensure commutative equality for sparse arrays. |
||
728 | if (!(result = size in a == size in b && eq(a[size], b[size], stack))) break; |
||
729 | } |
||
730 | } |
||
731 | } else { |
||
732 | // Objects with different constructors are not equivalent. |
||
733 | if ('constructor' in a != 'constructor' in b || a.constructor != b.constructor) return false; |
||
734 | // Deep compare objects. |
||
735 | for (var key in a) { |
||
736 | if (_.has(a, key)) { |
||
737 | // Count the expected number of properties. |
||
738 | size++; |
||
739 | // Deep compare each member. |
||
740 | if (!(result = _.has(b, key) && eq(a[key], b[key], stack))) break; |
||
741 | } |
||
742 | } |
||
743 | // Ensure that both objects contain the same number of properties. |
||
744 | if (result) { |
||
745 | for (key in b) { |
||
746 | if (_.has(b, key) && !(size--)) break; |
||
747 | } |
||
748 | result = !size; |
||
749 | } |
||
750 | } |
||
751 | // Remove the first object from the stack of traversed objects. |
||
752 | stack.pop(); |
||
753 | return result; |
||
754 | } |
||
755 | |||
756 | // Perform a deep comparison to check if two objects are equal. |
||
757 | _.isEqual = function(a, b) { |
||
758 | return eq(a, b, []); |
||
759 | }; |
||
760 | |||
761 | // Is a given array, string, or object empty? |
||
762 | // An "empty" object has no enumerable own-properties. |
||
763 | _.isEmpty = function(obj) { |
||
764 | if (_.isArray(obj) || _.isString(obj)) return obj.length === 0; |
||
765 | for (var key in obj) if (_.has(obj, key)) return false; |
||
766 | return true; |
||
767 | }; |
||
768 | |||
769 | // Is a given value a DOM element? |
||
770 | _.isElement = function(obj) { |
||
771 | return !!(obj && obj.nodeType == 1); |
||
772 | }; |
||
773 | |||
774 | // Is a given value an array? |
||
775 | // Delegates to ECMA5's native Array.isArray |
||
776 | _.isArray = nativeIsArray || function(obj) { |
||
777 | return toString.call(obj) == '[object Array]'; |
||
778 | }; |
||
779 | |||
780 | // Is a given variable an object? |
||
781 | _.isObject = function(obj) { |
||
782 | return obj === Object(obj); |
||
783 | }; |
||
784 | |||
785 | // Is a given variable an arguments object? |
||
786 | _.isArguments = function(obj) { |
||
787 | return toString.call(obj) == '[object Arguments]'; |
||
788 | }; |
||
789 | if (!_.isArguments(arguments)) { |
||
790 | _.isArguments = function(obj) { |
||
791 | return !!(obj && _.has(obj, 'callee')); |
||
792 | }; |
||
793 | } |
||
794 | |||
795 | // Is a given value a function? |
||
796 | _.isFunction = function(obj) { |
||
797 | return toString.call(obj) == '[object Function]'; |
||
798 | }; |
||
799 | |||
800 | // Is a given value a string? |
||
801 | _.isString = function(obj) { |
||
802 | return toString.call(obj) == '[object String]'; |
||
803 | }; |
||
804 | |||
805 | // Is a given value a number? |
||
806 | _.isNumber = function(obj) { |
||
807 | return toString.call(obj) == '[object Number]'; |
||
808 | }; |
||
809 | |||
810 | // Is the given value `NaN`? |
||
811 | _.isNaN = function(obj) { |
||
812 | // `NaN` is the only value for which `===` is not reflexive. |
||
813 | return obj !== obj; |
||
814 | }; |
||
815 | |||
816 | // Is a given value a boolean? |
||
817 | _.isBoolean = function(obj) { |
||
818 | return obj === true || obj === false || toString.call(obj) == '[object Boolean]'; |
||
819 | }; |
||
820 | |||
821 | // Is a given value a date? |
||
822 | _.isDate = function(obj) { |
||
823 | return toString.call(obj) == '[object Date]'; |
||
824 | }; |
||
825 | |||
826 | // Is the given value a regular expression? |
||
827 | _.isRegExp = function(obj) { |
||
828 | return toString.call(obj) == '[object RegExp]'; |
||
829 | }; |
||
830 | |||
831 | // Is a given value equal to null? |
||
832 | _.isNull = function(obj) { |
||
833 | return obj === null; |
||
834 | }; |
||
835 | |||
836 | // Is a given variable undefined? |
||
837 | _.isUndefined = function(obj) { |
||
838 | return obj === void 0; |
||
839 | }; |
||
840 | |||
841 | // Has own property? |
||
842 | _.has = function(obj, key) { |
||
843 | return hasOwnProperty.call(obj, key); |
||
844 | }; |
||
845 | |||
846 | // Utility Functions |
||
847 | // ----------------- |
||
848 | |||
849 | // Run Underscore.js in *noConflict* mode, returning the `_` variable to its |
||
850 | // previous owner. Returns a reference to the Underscore object. |
||
851 | _.noConflict = function() { |
||
852 | root._ = previousUnderscore; |
||
853 | return this; |
||
854 | }; |
||
855 | |||
856 | // Keep the identity function around for default iterators. |
||
857 | _.identity = function(value) { |
||
858 | return value; |
||
859 | }; |
||
860 | |||
861 | // Run a function **n** times. |
||
862 | _.times = function (n, iterator, context) { |
||
863 | for (var i = 0; i < n; i++) iterator.call(context, i); |
||
864 | }; |
||
865 | |||
866 | // Escape a string for HTML interpolation. |
||
867 | _.escape = function(string) { |
||
868 | return (''+string).replace(/&/g, '&').replace(/</g, '<').replace(/>/g, '>').replace(/"/g, '"').replace(/'/g, ''').replace(/\//g,'/'); |
||
869 | }; |
||
870 | |||
871 | // Add your own custom functions to the Underscore object, ensuring that |
||
872 | // they're correctly added to the OOP wrapper as well. |
||
873 | _.mixin = function(obj) { |
||
874 | each(_.functions(obj), function(name){ |
||
875 | addToWrapper(name, _[name] = obj[name]); |
||
876 | }); |
||
877 | }; |
||
878 | |||
879 | // Generate a unique integer id (unique within the entire client session). |
||
880 | // Useful for temporary DOM ids. |
||
881 | var idCounter = 0; |
||
882 | _.uniqueId = function(prefix) { |
||
883 | var id = idCounter++; |
||
884 | return prefix ? prefix + id : id; |
||
885 | }; |
||
886 | |||
887 | // By default, Underscore uses ERB-style template delimiters, change the |
||
888 | // following template settings to use alternative delimiters. |
||
889 | _.templateSettings = { |
||
890 | evaluate : /<%([\s\S]+?)%>/g, |
||
891 | interpolate : /<%=([\s\S]+?)%>/g, |
||
892 | escape : /<%-([\s\S]+?)%>/g |
||
893 | }; |
||
894 | |||
895 | // When customizing `templateSettings`, if you don't want to define an |
||
896 | // interpolation, evaluation or escaping regex, we need one that is |
||
897 | // guaranteed not to match. |
||
898 | var noMatch = /.^/; |
||
899 | |||
900 | // Within an interpolation, evaluation, or escaping, remove HTML escaping |
||
901 | // that had been previously added. |
||
902 | var unescape = function(code) { |
||
903 | return code.replace(/\\\\/g, '\\').replace(/\\'/g, "'"); |
||
904 | }; |
||
905 | |||
906 | // JavaScript micro-templating, similar to John Resig's implementation. |
||
907 | // Underscore templating handles arbitrary delimiters, preserves whitespace, |
||
908 | // and correctly escapes quotes within interpolated code. |
||
909 | _.template = function(str, data) { |
||
910 | var c = _.templateSettings; |
||
911 | var tmpl = 'var __p=[],print=function(){__p.push.apply(__p,arguments);};' + |
||
912 | 'with(obj||{}){__p.push(\'' + |
||
913 | str.replace(/\\/g, '\\\\') |
||
914 | .replace(/'/g, "\\'") |
||
915 | .replace(c.escape || noMatch, function(match, code) { |
||
916 | return "',_.escape(" + unescape(code) + "),'"; |
||
917 | }) |
||
918 | .replace(c.interpolate || noMatch, function(match, code) { |
||
919 | return "'," + unescape(code) + ",'"; |
||
920 | }) |
||
921 | .replace(c.evaluate || noMatch, function(match, code) { |
||
922 | return "');" + unescape(code).replace(/[\r\n\t]/g, ' ') + ";__p.push('"; |
||
923 | }) |
||
924 | .replace(/\r/g, '\\r') |
||
925 | .replace(/\n/g, '\\n') |
||
926 | .replace(/\t/g, '\\t') |
||
927 | + "');}return __p.join('');"; |
||
928 | var func = new Function('obj', '_', tmpl); |
||
929 | if (data) return func(data, _); |
||
930 | return function(data) { |
||
931 | return func.call(this, data, _); |
||
932 | }; |
||
933 | }; |
||
934 | |||
935 | // Add a "chain" function, which will delegate to the wrapper. |
||
936 | _.chain = function(obj) { |
||
937 | return _(obj).chain(); |
||
938 | }; |
||
939 | |||
940 | // The OOP Wrapper |
||
941 | // --------------- |
||
942 | |||
943 | // If Underscore is called as a function, it returns a wrapped object that |
||
944 | // can be used OO-style. This wrapper holds altered versions of all the |
||
945 | // underscore functions. Wrapped objects may be chained. |
||
946 | var wrapper = function(obj) { this._wrapped = obj; }; |
||
947 | |||
948 | // Expose `wrapper.prototype` as `_.prototype` |
||
949 | _.prototype = wrapper.prototype; |
||
950 | |||
951 | // Helper function to continue chaining intermediate results. |
||
952 | var result = function(obj, chain) { |
||
953 | return chain ? _(obj).chain() : obj; |
||
954 | }; |
||
955 | |||
956 | // A method to easily add functions to the OOP wrapper. |
||
957 | var addToWrapper = function(name, func) { |
||
958 | wrapper.prototype[name] = function() { |
||
959 | var args = slice.call(arguments); |
||
960 | unshift.call(args, this._wrapped); |
||
961 | return result(func.apply(_, args), this._chain); |
||
962 | }; |
||
963 | }; |
||
964 | |||
965 | // Add all of the Underscore functions to the wrapper object. |
||
966 | _.mixin(_); |
||
967 | |||
968 | // Add all mutator Array functions to the wrapper. |
||
969 | each(['pop', 'push', 'reverse', 'shift', 'sort', 'splice', 'unshift'], function(name) { |
||
970 | var method = ArrayProto[name]; |
||
971 | wrapper.prototype[name] = function() { |
||
972 | var wrapped = this._wrapped; |
||
973 | method.apply(wrapped, arguments); |
||
974 | var length = wrapped.length; |
||
975 | if ((name == 'shift' || name == 'splice') && length === 0) delete wrapped[0]; |
||
976 | return result(wrapped, this._chain); |
||
977 | }; |
||
978 | }); |
||
979 | |||
980 | // Add all accessor Array functions to the wrapper. |
||
981 | each(['concat', 'join', 'slice'], function(name) { |
||
982 | var method = ArrayProto[name]; |
||
983 | wrapper.prototype[name] = function() { |
||
984 | return result(method.apply(this._wrapped, arguments), this._chain); |
||
985 | }; |
||
986 | }); |
||
987 | |||
988 | // Start chaining a wrapped Underscore object. |
||
989 | wrapper.prototype.chain = function() { |
||
990 | this._chain = true; |
||
991 | return this; |
||
992 | }; |
||
993 | |||
994 | // Extracts the result from a wrapped and chained object. |
||
995 | wrapper.prototype.value = function() { |
||
996 | return this._wrapped; |
||
997 | }; |
||
998 | |||
999 | }).call(this); |
||
1000 |