1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
|
<!DOCTYPE html> <html> <head> <title>underscore.js</title> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> <link rel="stylesheet" media="all" href="docco.css" /> </head> <body> <div id="container"> <div id="background"></div> <table cellpadding="0" cellspacing="0"> <thead> <tr> <th class="docs"> <h1> underscore.js </h1> </th> <th class="code"> </th> </tr> </thead> <tbody> <tr id="section-1"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-1">¶</a> </div> <pre><code>Underscore.js 1.1.6
(c) 2011 Jeremy Ashkenas, DocumentCloud Inc.
Underscore is freely distributable under the MIT license.
Portions of Underscore are inspired or borrowed from Prototype,
Oliver Steele's Functional, and John Resig's Micro-Templating.
For all details and documentation:
http://documentcloud.github.com/underscore
</code></pre> </td> <td class="code"> <div class="highlight"><pre><span class="p">(</span><span class="kd">function</span><span class="p">()</span> <span class="p">{</span></pre></div> </td> </tr> <tr id="section-2"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-2">¶</a> </div> <h2>Baseline setup</h2> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-3"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-3">¶</a> </div> <p>Establish the root object, <code>window</code> in the browser, or <code>global</code> on the server.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">root</span> <span class="o">=</span> <span class="k">this</span><span class="p">;</span></pre></div> </td> </tr> <tr id="section-4"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-4">¶</a> </div> <p>Save the previous value of the <code>_</code> variable.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">previousUnderscore</span> <span class="o">=</span> <span class="nx">root</span><span class="p">.</span><span class="nx">_</span><span class="p">;</span></pre></div> </td> </tr> <tr id="section-5"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-5">¶</a> </div> <p>Establish the object that gets returned to break out of a loop iteration.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">breaker</span> <span class="o">=</span> <span class="p">{};</span></pre></div> </td> </tr> <tr id="section-6"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-6">¶</a> </div> <p>Save bytes in the minified (but not gzipped) version:</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">ArrayProto</span> <span class="o">=</span> <span class="nb">Array</span><span class="p">.</span><span class="nx">prototype</span><span class="p">,</span> <span class="nx">ObjProto</span> <span class="o">=</span> <span class="nb">Object</span><span class="p">.</span><span class="nx">prototype</span><span class="p">,</span> <span class="nx">FuncProto</span> <span class="o">=</span> <span class="nb">Function</span><span class="p">.</span><span class="nx">prototype</span><span class="p">;</span></pre></div> </td> </tr> <tr id="section-7"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-7">¶</a> </div> <p>Create quick reference variables for speed access to core prototypes.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">slice</span> <span class="o">=</span> <span class="nx">ArrayProto</span><span class="p">.</span><span class="nx">slice</span><span class="p">,</span>
<span class="nx">unshift</span> <span class="o">=</span> <span class="nx">ArrayProto</span><span class="p">.</span><span class="nx">unshift</span><span class="p">,</span>
<span class="nx">toString</span> <span class="o">=</span> <span class="nx">ObjProto</span><span class="p">.</span><span class="nx">toString</span><span class="p">,</span>
<span class="nx">hasOwnProperty</span> <span class="o">=</span> <span class="nx">ObjProto</span><span class="p">.</span><span class="nx">hasOwnProperty</span><span class="p">;</span></pre></div> </td> </tr> <tr id="section-8"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-8">¶</a> </div> <p>All <strong>ECMAScript 5</strong> native function implementations that we hope to use
are declared here.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span>
<span class="nx">nativeForEach</span> <span class="o">=</span> <span class="nx">ArrayProto</span><span class="p">.</span><span class="nx">forEach</span><span class="p">,</span>
<span class="nx">nativeMap</span> <span class="o">=</span> <span class="nx">ArrayProto</span><span class="p">.</span><span class="nx">map</span><span class="p">,</span>
<span class="nx">nativeReduce</span> <span class="o">=</span> <span class="nx">ArrayProto</span><span class="p">.</span><span class="nx">reduce</span><span class="p">,</span>
<span class="nx">nativeReduceRight</span> <span class="o">=</span> <span class="nx">ArrayProto</span><span class="p">.</span><span class="nx">reduceRight</span><span class="p">,</span>
<span class="nx">nativeFilter</span> <span class="o">=</span> <span class="nx">ArrayProto</span><span class="p">.</span><span class="nx">filter</span><span class="p">,</span>
<span class="nx">nativeEvery</span> <span class="o">=</span> <span class="nx">ArrayProto</span><span class="p">.</span><span class="nx">every</span><span class="p">,</span>
<span class="nx">nativeSome</span> <span class="o">=</span> <span class="nx">ArrayProto</span><span class="p">.</span><span class="nx">some</span><span class="p">,</span>
<span class="nx">nativeIndexOf</span> <span class="o">=</span> <span class="nx">ArrayProto</span><span class="p">.</span><span class="nx">indexOf</span><span class="p">,</span>
<span class="nx">nativeLastIndexOf</span> <span class="o">=</span> <span class="nx">ArrayProto</span><span class="p">.</span><span class="nx">lastIndexOf</span><span class="p">,</span>
<span class="nx">nativeIsArray</span> <span class="o">=</span> <span class="nb">Array</span><span class="p">.</span><span class="nx">isArray</span><span class="p">,</span>
<span class="nx">nativeKeys</span> <span class="o">=</span> <span class="nb">Object</span><span class="p">.</span><span class="nx">keys</span><span class="p">,</span>
<span class="nx">nativeBind</span> <span class="o">=</span> <span class="nx">FuncProto</span><span class="p">.</span><span class="nx">bind</span><span class="p">;</span></pre></div> </td> </tr> <tr id="section-9"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-9">¶</a> </div> <p>Create a safe reference to the Underscore object for use below.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">_</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span> <span class="k">return</span> <span class="k">new</span> <span class="nx">wrapper</span><span class="p">(</span><span class="nx">obj</span><span class="p">);</span> <span class="p">};</span></pre></div> </td> </tr> <tr id="section-10"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-10">¶</a> </div> <p>Export the Underscore object for <strong>CommonJS</strong>, with backwards-compatibility
for the old <code>require()</code> API. If we're not in CommonJS, add <code>_</code> to the
global object.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="k">if</span> <span class="p">(</span><span class="k">typeof</span> <span class="nx">module</span> <span class="o">!==</span> <span class="s1">'undefined'</span> <span class="o">&&</span> <span class="nx">module</span><span class="p">.</span><span class="nx">exports</span><span class="p">)</span> <span class="p">{</span>
<span class="nx">module</span><span class="p">.</span><span class="nx">exports</span> <span class="o">=</span> <span class="nx">_</span><span class="p">;</span>
<span class="nx">_</span><span class="p">.</span><span class="nx">_</span> <span class="o">=</span> <span class="nx">_</span><span class="p">;</span>
<span class="p">}</span> <span class="k">else</span> <span class="p">{</span>
<span class="nx">root</span><span class="p">.</span><span class="nx">_</span> <span class="o">=</span> <span class="nx">_</span><span class="p">;</span>
<span class="p">}</span></pre></div> </td> </tr> <tr id="section-11"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-11">¶</a> </div> <p>Current version.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">VERSION</span> <span class="o">=</span> <span class="s1">'1.1.6'</span><span class="p">;</span></pre></div> </td> </tr> <tr id="section-12"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-12">¶</a> </div> <h2>Collection Functions</h2> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-13"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-13">¶</a> </div> <p>The cornerstone, an <code>each</code> implementation, aka <code>forEach</code>.
Handles objects implementing <code>forEach</code>, arrays, and raw objects.
Delegates to <strong>ECMAScript 5</strong>'s native <code>forEach</code> if available.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">each</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">each</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">forEach</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">iterator</span><span class="p">,</span> <span class="nx">context</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">obj</span> <span class="o">==</span> <span class="kc">null</span><span class="p">)</span> <span class="k">return</span><span class="p">;</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">nativeForEach</span> <span class="o">&&</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">forEach</span> <span class="o">===</span> <span class="nx">nativeForEach</span><span class="p">)</span> <span class="p">{</span>
<span class="nx">obj</span><span class="p">.</span><span class="nx">forEach</span><span class="p">(</span><span class="nx">iterator</span><span class="p">,</span> <span class="nx">context</span><span class="p">);</span>
<span class="p">}</span> <span class="k">else</span> <span class="k">if</span> <span class="p">(</span><span class="nx">_</span><span class="p">.</span><span class="nx">isNumber</span><span class="p">(</span><span class="nx">obj</span><span class="p">.</span><span class="nx">length</span><span class="p">))</span> <span class="p">{</span>
<span class="k">for</span> <span class="p">(</span><span class="kd">var</span> <span class="nx">i</span> <span class="o">=</span> <span class="mi">0</span><span class="p">,</span> <span class="nx">l</span> <span class="o">=</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">length</span><span class="p">;</span> <span class="nx">i</span> <span class="o"><</span> <span class="nx">l</span><span class="p">;</span> <span class="nx">i</span><span class="o">++</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">iterator</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">context</span><span class="p">,</span> <span class="nx">obj</span><span class="p">[</span><span class="nx">i</span><span class="p">],</span> <span class="nx">i</span><span class="p">,</span> <span class="nx">obj</span><span class="p">)</span> <span class="o">===</span> <span class="nx">breaker</span><span class="p">)</span> <span class="k">return</span><span class="p">;</span>
<span class="p">}</span>
<span class="p">}</span> <span class="k">else</span> <span class="p">{</span>
<span class="k">for</span> <span class="p">(</span><span class="kd">var</span> <span class="nx">key</span> <span class="k">in</span> <span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">hasOwnProperty</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">key</span><span class="p">))</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">iterator</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">context</span><span class="p">,</span> <span class="nx">obj</span><span class="p">[</span><span class="nx">key</span><span class="p">],</span> <span class="nx">key</span><span class="p">,</span> <span class="nx">obj</span><span class="p">)</span> <span class="o">===</span> <span class="nx">breaker</span><span class="p">)</span> <span class="k">return</span><span class="p">;</span>
<span class="p">}</span>
<span class="p">}</span>
<span class="p">}</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-14"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-14">¶</a> </div> <p>Return the results of applying the iterator to each element.
Delegates to <strong>ECMAScript 5</strong>'s native <code>map</code> if available.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">map</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">iterator</span><span class="p">,</span> <span class="nx">context</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">results</span> <span class="o">=</span> <span class="p">[];</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">obj</span> <span class="o">==</span> <span class="kc">null</span><span class="p">)</span> <span class="k">return</span> <span class="nx">results</span><span class="p">;</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">nativeMap</span> <span class="o">&&</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">map</span> <span class="o">===</span> <span class="nx">nativeMap</span><span class="p">)</span> <span class="k">return</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">map</span><span class="p">(</span><span class="nx">iterator</span><span class="p">,</span> <span class="nx">context</span><span class="p">);</span>
<span class="nx">each</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">value</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">list</span><span class="p">)</span> <span class="p">{</span>
<span class="nx">results</span><span class="p">[</span><span class="nx">results</span><span class="p">.</span><span class="nx">length</span><span class="p">]</span> <span class="o">=</span> <span class="nx">iterator</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">context</span><span class="p">,</span> <span class="nx">value</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">list</span><span class="p">);</span>
<span class="p">});</span>
<span class="k">return</span> <span class="nx">results</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-15"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-15">¶</a> </div> <p><strong>Reduce</strong> builds up a single result from a list of values, aka <code>inject</code>,
or <code>foldl</code>. Delegates to <strong>ECMAScript 5</strong>'s native <code>reduce</code> if available.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">reduce</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">foldl</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">inject</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">iterator</span><span class="p">,</span> <span class="nx">memo</span><span class="p">,</span> <span class="nx">context</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">initial</span> <span class="o">=</span> <span class="nx">memo</span> <span class="o">!==</span> <span class="k">void</span> <span class="mi">0</span><span class="p">;</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">obj</span> <span class="o">==</span> <span class="kc">null</span><span class="p">)</span> <span class="nx">obj</span> <span class="o">=</span> <span class="p">[];</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">nativeReduce</span> <span class="o">&&</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">reduce</span> <span class="o">===</span> <span class="nx">nativeReduce</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">context</span><span class="p">)</span> <span class="nx">iterator</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">bind</span><span class="p">(</span><span class="nx">iterator</span><span class="p">,</span> <span class="nx">context</span><span class="p">);</span>
<span class="k">return</span> <span class="nx">initial</span> <span class="o">?</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">reduce</span><span class="p">(</span><span class="nx">iterator</span><span class="p">,</span> <span class="nx">memo</span><span class="p">)</span> <span class="o">:</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">reduce</span><span class="p">(</span><span class="nx">iterator</span><span class="p">);</span>
<span class="p">}</span>
<span class="nx">each</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">value</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">list</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="o">!</span><span class="nx">initial</span> <span class="o">&&</span> <span class="nx">index</span> <span class="o">===</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="nx">memo</span> <span class="o">=</span> <span class="nx">value</span><span class="p">;</span>
<span class="nx">initial</span> <span class="o">=</span> <span class="kc">true</span><span class="p">;</span>
<span class="p">}</span> <span class="k">else</span> <span class="p">{</span>
<span class="nx">memo</span> <span class="o">=</span> <span class="nx">iterator</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">context</span><span class="p">,</span> <span class="nx">memo</span><span class="p">,</span> <span class="nx">value</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">list</span><span class="p">);</span>
<span class="p">}</span>
<span class="p">});</span>
<span class="k">if</span> <span class="p">(</span><span class="o">!</span><span class="nx">initial</span><span class="p">)</span> <span class="k">throw</span> <span class="k">new</span> <span class="nx">TypeError</span><span class="p">(</span><span class="s2">"Reduce of empty array with no initial value"</span><span class="p">);</span>
<span class="k">return</span> <span class="nx">memo</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-16"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-16">¶</a> </div> <p>The right-associative version of reduce, also known as <code>foldr</code>.
Delegates to <strong>ECMAScript 5</strong>'s native <code>reduceRight</code> if available.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">reduceRight</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">foldr</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">iterator</span><span class="p">,</span> <span class="nx">memo</span><span class="p">,</span> <span class="nx">context</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">obj</span> <span class="o">==</span> <span class="kc">null</span><span class="p">)</span> <span class="nx">obj</span> <span class="o">=</span> <span class="p">[];</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">nativeReduceRight</span> <span class="o">&&</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">reduceRight</span> <span class="o">===</span> <span class="nx">nativeReduceRight</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">context</span><span class="p">)</span> <span class="nx">iterator</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">bind</span><span class="p">(</span><span class="nx">iterator</span><span class="p">,</span> <span class="nx">context</span><span class="p">);</span>
<span class="k">return</span> <span class="nx">memo</span> <span class="o">!==</span> <span class="k">void</span> <span class="mi">0</span> <span class="o">?</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">reduceRight</span><span class="p">(</span><span class="nx">iterator</span><span class="p">,</span> <span class="nx">memo</span><span class="p">)</span> <span class="o">:</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">reduceRight</span><span class="p">(</span><span class="nx">iterator</span><span class="p">);</span>
<span class="p">}</span>
<span class="kd">var</span> <span class="nx">reversed</span> <span class="o">=</span> <span class="p">(</span><span class="nx">_</span><span class="p">.</span><span class="nx">isArray</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="o">?</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">slice</span><span class="p">()</span> <span class="o">:</span> <span class="nx">_</span><span class="p">.</span><span class="nx">toArray</span><span class="p">(</span><span class="nx">obj</span><span class="p">)).</span><span class="nx">reverse</span><span class="p">();</span>
<span class="k">return</span> <span class="nx">_</span><span class="p">.</span><span class="nx">reduce</span><span class="p">(</span><span class="nx">reversed</span><span class="p">,</span> <span class="nx">iterator</span><span class="p">,</span> <span class="nx">memo</span><span class="p">,</span> <span class="nx">context</span><span class="p">);</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-17"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-17">¶</a> </div> <p>Return the first value which passes a truth test. Aliased as <code>detect</code>.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">find</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">detect</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">iterator</span><span class="p">,</span> <span class="nx">context</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">result</span><span class="p">;</span>
<span class="nx">any</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">value</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">list</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">iterator</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">context</span><span class="p">,</span> <span class="nx">value</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">list</span><span class="p">))</span> <span class="p">{</span>
<span class="nx">result</span> <span class="o">=</span> <span class="nx">value</span><span class="p">;</span>
<span class="k">return</span> <span class="kc">true</span><span class="p">;</span>
<span class="p">}</span>
<span class="p">});</span>
<span class="k">return</span> <span class="nx">result</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-18"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-18">¶</a> </div> <p>Return all the elements that pass a truth test.
Delegates to <strong>ECMAScript 5</strong>'s native <code>filter</code> if available.
Aliased as <code>select</code>.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">filter</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">select</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">iterator</span><span class="p">,</span> <span class="nx">context</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">results</span> <span class="o">=</span> <span class="p">[];</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">obj</span> <span class="o">==</span> <span class="kc">null</span><span class="p">)</span> <span class="k">return</span> <span class="nx">results</span><span class="p">;</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">nativeFilter</span> <span class="o">&&</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">filter</span> <span class="o">===</span> <span class="nx">nativeFilter</span><span class="p">)</span> <span class="k">return</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">filter</span><span class="p">(</span><span class="nx">iterator</span><span class="p">,</span> <span class="nx">context</span><span class="p">);</span>
<span class="nx">each</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">value</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">list</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">iterator</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">context</span><span class="p">,</span> <span class="nx">value</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">list</span><span class="p">))</span> <span class="nx">results</span><span class="p">[</span><span class="nx">results</span><span class="p">.</span><span class="nx">length</span><span class="p">]</span> <span class="o">=</span> <span class="nx">value</span><span class="p">;</span>
<span class="p">});</span>
<span class="k">return</span> <span class="nx">results</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-19"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-19">¶</a> </div> <p>Return all the elements for which a truth test fails.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">reject</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">iterator</span><span class="p">,</span> <span class="nx">context</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">results</span> <span class="o">=</span> <span class="p">[];</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">obj</span> <span class="o">==</span> <span class="kc">null</span><span class="p">)</span> <span class="k">return</span> <span class="nx">results</span><span class="p">;</span>
<span class="nx">each</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">value</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">list</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="o">!</span><span class="nx">iterator</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">context</span><span class="p">,</span> <span class="nx">value</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">list</span><span class="p">))</span> <span class="nx">results</span><span class="p">[</span><span class="nx">results</span><span class="p">.</span><span class="nx">length</span><span class="p">]</span> <span class="o">=</span> <span class="nx">value</span><span class="p">;</span>
<span class="p">});</span>
<span class="k">return</span> <span class="nx">results</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-20"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-20">¶</a> </div> <p>Determine whether all of the elements match a truth test.
Delegates to <strong>ECMAScript 5</strong>'s native <code>every</code> if available.
Aliased as <code>all</code>.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">every</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">all</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">iterator</span><span class="p">,</span> <span class="nx">context</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">result</span> <span class="o">=</span> <span class="kc">true</span><span class="p">;</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">obj</span> <span class="o">==</span> <span class="kc">null</span><span class="p">)</span> <span class="k">return</span> <span class="nx">result</span><span class="p">;</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">nativeEvery</span> <span class="o">&&</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">every</span> <span class="o">===</span> <span class="nx">nativeEvery</span><span class="p">)</span> <span class="k">return</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">every</span><span class="p">(</span><span class="nx">iterator</span><span class="p">,</span> <span class="nx">context</span><span class="p">);</span>
<span class="nx">each</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">value</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">list</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="o">!</span><span class="p">(</span><span class="nx">result</span> <span class="o">=</span> <span class="nx">result</span> <span class="o">&&</span> <span class="nx">iterator</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">context</span><span class="p">,</span> <span class="nx">value</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">list</span><span class="p">)))</span> <span class="k">return</span> <span class="nx">breaker</span><span class="p">;</span>
<span class="p">});</span>
<span class="k">return</span> <span class="nx">result</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-21"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-21">¶</a> </div> <p>Determine if at least one element in the object matches a truth test.
Delegates to <strong>ECMAScript 5</strong>'s native <code>some</code> if available.
Aliased as <code>any</code>.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">any</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">some</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">any</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">iterator</span><span class="p">,</span> <span class="nx">context</span><span class="p">)</span> <span class="p">{</span>
<span class="nx">iterator</span> <span class="o">||</span> <span class="p">(</span><span class="nx">iterator</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">identity</span><span class="p">);</span>
<span class="kd">var</span> <span class="nx">result</span> <span class="o">=</span> <span class="kc">false</span><span class="p">;</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">obj</span> <span class="o">==</span> <span class="kc">null</span><span class="p">)</span> <span class="k">return</span> <span class="nx">result</span><span class="p">;</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">nativeSome</span> <span class="o">&&</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">some</span> <span class="o">===</span> <span class="nx">nativeSome</span><span class="p">)</span> <span class="k">return</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">some</span><span class="p">(</span><span class="nx">iterator</span><span class="p">,</span> <span class="nx">context</span><span class="p">);</span>
<span class="nx">each</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">value</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">list</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">result</span> <span class="o">=</span> <span class="nx">iterator</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">context</span><span class="p">,</span> <span class="nx">value</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">list</span><span class="p">))</span> <span class="k">return</span> <span class="nx">breaker</span><span class="p">;</span>
<span class="p">});</span>
<span class="k">return</span> <span class="nx">result</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-22"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-22">¶</a> </div> <p>Determine if a given value is included in the array or object using <code>===</code>.
Aliased as <code>contains</code>.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">include</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">contains</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">target</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">found</span> <span class="o">=</span> <span class="kc">false</span><span class="p">;</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">obj</span> <span class="o">==</span> <span class="kc">null</span><span class="p">)</span> <span class="k">return</span> <span class="nx">found</span><span class="p">;</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">nativeIndexOf</span> <span class="o">&&</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">indexOf</span> <span class="o">===</span> <span class="nx">nativeIndexOf</span><span class="p">)</span> <span class="k">return</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">indexOf</span><span class="p">(</span><span class="nx">target</span><span class="p">)</span> <span class="o">!=</span> <span class="o">-</span><span class="mi">1</span><span class="p">;</span>
<span class="nx">any</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">value</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">found</span> <span class="o">=</span> <span class="nx">value</span> <span class="o">===</span> <span class="nx">target</span><span class="p">)</span> <span class="k">return</span> <span class="kc">true</span><span class="p">;</span>
<span class="p">});</span>
<span class="k">return</span> <span class="nx">found</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-23"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-23">¶</a> </div> <p>Invoke a method (with arguments) on every item in a collection.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">invoke</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">method</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">args</span> <span class="o">=</span> <span class="nx">slice</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">arguments</span><span class="p">,</span> <span class="mi">2</span><span class="p">);</span>
<span class="k">return</span> <span class="nx">_</span><span class="p">.</span><span class="nx">map</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">value</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="p">(</span><span class="nx">method</span><span class="p">.</span><span class="nx">call</span> <span class="o">?</span> <span class="nx">method</span> <span class="o">||</span> <span class="nx">value</span> <span class="o">:</span> <span class="nx">value</span><span class="p">[</span><span class="nx">method</span><span class="p">]).</span><span class="nx">apply</span><span class="p">(</span><span class="nx">value</span><span class="p">,</span> <span class="nx">args</span><span class="p">);</span>
<span class="p">});</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-24"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-24">¶</a> </div> <p>Convenience version of a common use case of <code>map</code>: fetching a property.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">pluck</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">key</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">_</span><span class="p">.</span><span class="nx">map</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">value</span><span class="p">){</span> <span class="k">return</span> <span class="nx">value</span><span class="p">[</span><span class="nx">key</span><span class="p">];</span> <span class="p">});</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-25"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-25">¶</a> </div> <p>Return the maximum element or (element-based computation).</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">max</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">iterator</span><span class="p">,</span> <span class="nx">context</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="o">!</span><span class="nx">iterator</span> <span class="o">&&</span> <span class="nx">_</span><span class="p">.</span><span class="nx">isArray</span><span class="p">(</span><span class="nx">obj</span><span class="p">))</span> <span class="k">return</span> <span class="nb">Math</span><span class="p">.</span><span class="nx">max</span><span class="p">.</span><span class="nx">apply</span><span class="p">(</span><span class="nb">Math</span><span class="p">,</span> <span class="nx">obj</span><span class="p">);</span>
<span class="kd">var</span> <span class="nx">result</span> <span class="o">=</span> <span class="p">{</span><span class="nx">computed</span> <span class="o">:</span> <span class="o">-</span><span class="kc">Infinity</span><span class="p">};</span>
<span class="nx">each</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">value</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">list</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">computed</span> <span class="o">=</span> <span class="nx">iterator</span> <span class="o">?</span> <span class="nx">iterator</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">context</span><span class="p">,</span> <span class="nx">value</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">list</span><span class="p">)</span> <span class="o">:</span> <span class="nx">value</span><span class="p">;</span>
<span class="nx">computed</span> <span class="o">>=</span> <span class="nx">result</span><span class="p">.</span><span class="nx">computed</span> <span class="o">&&</span> <span class="p">(</span><span class="nx">result</span> <span class="o">=</span> <span class="p">{</span><span class="nx">value</span> <span class="o">:</span> <span class="nx">value</span><span class="p">,</span> <span class="nx">computed</span> <span class="o">:</span> <span class="nx">computed</span><span class="p">});</span>
<span class="p">});</span>
<span class="k">return</span> <span class="nx">result</span><span class="p">.</span><span class="nx">value</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-26"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-26">¶</a> </div> <p>Return the minimum element (or element-based computation).</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">min</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">iterator</span><span class="p">,</span> <span class="nx">context</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="o">!</span><span class="nx">iterator</span> <span class="o">&&</span> <span class="nx">_</span><span class="p">.</span><span class="nx">isArray</span><span class="p">(</span><span class="nx">obj</span><span class="p">))</span> <span class="k">return</span> <span class="nb">Math</span><span class="p">.</span><span class="nx">min</span><span class="p">.</span><span class="nx">apply</span><span class="p">(</span><span class="nb">Math</span><span class="p">,</span> <span class="nx">obj</span><span class="p">);</span>
<span class="kd">var</span> <span class="nx">result</span> <span class="o">=</span> <span class="p">{</span><span class="nx">computed</span> <span class="o">:</span> <span class="kc">Infinity</span><span class="p">};</span>
<span class="nx">each</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">value</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">list</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">computed</span> <span class="o">=</span> <span class="nx">iterator</span> <span class="o">?</span> <span class="nx">iterator</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">context</span><span class="p">,</span> <span class="nx">value</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">list</span><span class="p">)</span> <span class="o">:</span> <span class="nx">value</span><span class="p">;</span>
<span class="nx">computed</span> <span class="o"><</span> <span class="nx">result</span><span class="p">.</span><span class="nx">computed</span> <span class="o">&&</span> <span class="p">(</span><span class="nx">result</span> <span class="o">=</span> <span class="p">{</span><span class="nx">value</span> <span class="o">:</span> <span class="nx">value</span><span class="p">,</span> <span class="nx">computed</span> <span class="o">:</span> <span class="nx">computed</span><span class="p">});</span>
<span class="p">});</span>
<span class="k">return</span> <span class="nx">result</span><span class="p">.</span><span class="nx">value</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-27"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-27">¶</a> </div> <p>Sort the object's values by a criterion produced by an iterator.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">sortBy</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">iterator</span><span class="p">,</span> <span class="nx">context</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">_</span><span class="p">.</span><span class="nx">pluck</span><span class="p">(</span><span class="nx">_</span><span class="p">.</span><span class="nx">map</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">value</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">list</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="p">{</span>
<span class="nx">value</span> <span class="o">:</span> <span class="nx">value</span><span class="p">,</span>
<span class="nx">criteria</span> <span class="o">:</span> <span class="nx">iterator</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">context</span><span class="p">,</span> <span class="nx">value</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">list</span><span class="p">)</span>
<span class="p">};</span>
<span class="p">}).</span><span class="nx">sort</span><span class="p">(</span><span class="kd">function</span><span class="p">(</span><span class="nx">left</span><span class="p">,</span> <span class="nx">right</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">a</span> <span class="o">=</span> <span class="nx">left</span><span class="p">.</span><span class="nx">criteria</span><span class="p">,</span> <span class="nx">b</span> <span class="o">=</span> <span class="nx">right</span><span class="p">.</span><span class="nx">criteria</span><span class="p">;</span>
<span class="k">return</span> <span class="nx">a</span> <span class="o"><</span> <span class="nx">b</span> <span class="o">?</span> <span class="o">-</span><span class="mi">1</span> <span class="o">:</span> <span class="nx">a</span> <span class="o">></span> <span class="nx">b</span> <span class="o">?</span> <span class="mi">1</span> <span class="o">:</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}),</span> <span class="s1">'value'</span><span class="p">);</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-28"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-28">¶</a> </div> <p>Use a comparator function to figure out at what index an object should
be inserted so as to maintain order. Uses binary search.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">sortedIndex</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">array</span><span class="p">,</span> <span class="nx">obj</span><span class="p">,</span> <span class="nx">iterator</span><span class="p">)</span> <span class="p">{</span>
<span class="nx">iterator</span> <span class="o">||</span> <span class="p">(</span><span class="nx">iterator</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">identity</span><span class="p">);</span>
<span class="kd">var</span> <span class="nx">low</span> <span class="o">=</span> <span class="mi">0</span><span class="p">,</span> <span class="nx">high</span> <span class="o">=</span> <span class="nx">array</span><span class="p">.</span><span class="nx">length</span><span class="p">;</span>
<span class="k">while</span> <span class="p">(</span><span class="nx">low</span> <span class="o"><</span> <span class="nx">high</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">mid</span> <span class="o">=</span> <span class="p">(</span><span class="nx">low</span> <span class="o">+</span> <span class="nx">high</span><span class="p">)</span> <span class="o">>></span> <span class="mi">1</span><span class="p">;</span>
<span class="nx">iterator</span><span class="p">(</span><span class="nx">array</span><span class="p">[</span><span class="nx">mid</span><span class="p">])</span> <span class="o"><</span> <span class="nx">iterator</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="o">?</span> <span class="nx">low</span> <span class="o">=</span> <span class="nx">mid</span> <span class="o">+</span> <span class="mi">1</span> <span class="o">:</span> <span class="nx">high</span> <span class="o">=</span> <span class="nx">mid</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="nx">low</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-29"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-29">¶</a> </div> <p>Safely convert anything iterable into a real, live array.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">toArray</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">iterable</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="o">!</span><span class="nx">iterable</span><span class="p">)</span> <span class="k">return</span> <span class="p">[];</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">iterable</span><span class="p">.</span><span class="nx">toArray</span><span class="p">)</span> <span class="k">return</span> <span class="nx">iterable</span><span class="p">.</span><span class="nx">toArray</span><span class="p">();</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">_</span><span class="p">.</span><span class="nx">isArray</span><span class="p">(</span><span class="nx">iterable</span><span class="p">))</span> <span class="k">return</span> <span class="nx">iterable</span><span class="p">;</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">_</span><span class="p">.</span><span class="nx">isArguments</span><span class="p">(</span><span class="nx">iterable</span><span class="p">))</span> <span class="k">return</span> <span class="nx">slice</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">iterable</span><span class="p">);</span>
<span class="k">return</span> <span class="nx">_</span><span class="p">.</span><span class="nx">values</span><span class="p">(</span><span class="nx">iterable</span><span class="p">);</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-30"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-30">¶</a> </div> <p>Return the number of elements in an object.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">size</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">_</span><span class="p">.</span><span class="nx">toArray</span><span class="p">(</span><span class="nx">obj</span><span class="p">).</span><span class="nx">length</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-31"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-31">¶</a> </div> <h2>Array Functions</h2> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-32"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-32">¶</a> </div> <p>Get the first element of an array. Passing <strong>n</strong> will return the first N
values in the array. Aliased as <code>head</code>. The <strong>guard</strong> check allows it to work
with <code>_.map</code>.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">first</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">head</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">array</span><span class="p">,</span> <span class="nx">n</span><span class="p">,</span> <span class="nx">guard</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="p">(</span><span class="nx">n</span> <span class="o">!=</span> <span class="kc">null</span><span class="p">)</span> <span class="o">&&</span> <span class="o">!</span><span class="nx">guard</span> <span class="o">?</span> <span class="nx">slice</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">array</span><span class="p">,</span> <span class="mi">0</span><span class="p">,</span> <span class="nx">n</span><span class="p">)</span> <span class="o">:</span> <span class="nx">array</span><span class="p">[</span><span class="mi">0</span><span class="p">];</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-33"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-33">¶</a> </div> <p>Returns everything but the first entry of the array. Aliased as <code>tail</code>.
Especially useful on the arguments object. Passing an <strong>index</strong> will return
the rest of the values in the array from that index onward. The <strong>guard</strong>
check allows it to work with <code>_.map</code>.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">rest</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">tail</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">array</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">guard</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">slice</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">array</span><span class="p">,</span> <span class="p">(</span><span class="nx">index</span> <span class="o">==</span> <span class="kc">null</span><span class="p">)</span> <span class="o">||</span> <span class="nx">guard</span> <span class="o">?</span> <span class="mi">1</span> <span class="o">:</span> <span class="nx">index</span><span class="p">);</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-34"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-34">¶</a> </div> <p>Get the last element of an array.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">last</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">array</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">array</span><span class="p">[</span><span class="nx">array</span><span class="p">.</span><span class="nx">length</span> <span class="o">-</span> <span class="mi">1</span><span class="p">];</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-35"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-35">¶</a> </div> <p>Trim out all falsy values from an array.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">compact</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">array</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">_</span><span class="p">.</span><span class="nx">filter</span><span class="p">(</span><span class="nx">array</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">value</span><span class="p">){</span> <span class="k">return</span> <span class="o">!!</span><span class="nx">value</span><span class="p">;</span> <span class="p">});</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-36"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-36">¶</a> </div> <p>Return a completely flattened version of an array.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">flatten</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">array</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">_</span><span class="p">.</span><span class="nx">reduce</span><span class="p">(</span><span class="nx">array</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">memo</span><span class="p">,</span> <span class="nx">value</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">_</span><span class="p">.</span><span class="nx">isArray</span><span class="p">(</span><span class="nx">value</span><span class="p">))</span> <span class="k">return</span> <span class="nx">memo</span><span class="p">.</span><span class="nx">concat</span><span class="p">(</span><span class="nx">_</span><span class="p">.</span><span class="nx">flatten</span><span class="p">(</span><span class="nx">value</span><span class="p">));</span>
<span class="nx">memo</span><span class="p">[</span><span class="nx">memo</span><span class="p">.</span><span class="nx">length</span><span class="p">]</span> <span class="o">=</span> <span class="nx">value</span><span class="p">;</span>
<span class="k">return</span> <span class="nx">memo</span><span class="p">;</span>
<span class="p">},</span> <span class="p">[]);</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-37"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-37">¶</a> </div> <p>Return a version of the array that does not contain the specified value(s).</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">without</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">array</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">values</span> <span class="o">=</span> <span class="nx">slice</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">arguments</span><span class="p">,</span> <span class="mi">1</span><span class="p">);</span>
<span class="k">return</span> <span class="nx">_</span><span class="p">.</span><span class="nx">filter</span><span class="p">(</span><span class="nx">array</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">value</span><span class="p">){</span> <span class="k">return</span> <span class="o">!</span><span class="nx">_</span><span class="p">.</span><span class="nx">include</span><span class="p">(</span><span class="nx">values</span><span class="p">,</span> <span class="nx">value</span><span class="p">);</span> <span class="p">});</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-38"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-38">¶</a> </div> <p>Produce a duplicate-free version of the array. If the array has already
been sorted, you have the option of using a faster algorithm.
Aliased as <code>unique</code>.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">uniq</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">unique</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">array</span><span class="p">,</span> <span class="nx">isSorted</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">_</span><span class="p">.</span><span class="nx">reduce</span><span class="p">(</span><span class="nx">array</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">memo</span><span class="p">,</span> <span class="nx">el</span><span class="p">,</span> <span class="nx">i</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="mi">0</span> <span class="o">==</span> <span class="nx">i</span> <span class="o">||</span> <span class="p">(</span><span class="nx">isSorted</span> <span class="o">===</span> <span class="kc">true</span> <span class="o">?</span> <span class="nx">_</span><span class="p">.</span><span class="nx">last</span><span class="p">(</span><span class="nx">memo</span><span class="p">)</span> <span class="o">!=</span> <span class="nx">el</span> <span class="o">:</span> <span class="o">!</span><span class="nx">_</span><span class="p">.</span><span class="nx">include</span><span class="p">(</span><span class="nx">memo</span><span class="p">,</span> <span class="nx">el</span><span class="p">)))</span> <span class="nx">memo</span><span class="p">[</span><span class="nx">memo</span><span class="p">.</span><span class="nx">length</span><span class="p">]</span> <span class="o">=</span> <span class="nx">el</span><span class="p">;</span>
<span class="k">return</span> <span class="nx">memo</span><span class="p">;</span>
<span class="p">},</span> <span class="p">[]);</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-39"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-39">¶</a> </div> <p>Produce an array that contains every item shared between all the
passed-in arrays.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">intersect</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">array</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">rest</span> <span class="o">=</span> <span class="nx">slice</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">arguments</span><span class="p">,</span> <span class="mi">1</span><span class="p">);</span>
<span class="k">return</span> <span class="nx">_</span><span class="p">.</span><span class="nx">filter</span><span class="p">(</span><span class="nx">_</span><span class="p">.</span><span class="nx">uniq</span><span class="p">(</span><span class="nx">array</span><span class="p">),</span> <span class="kd">function</span><span class="p">(</span><span class="nx">item</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">_</span><span class="p">.</span><span class="nx">every</span><span class="p">(</span><span class="nx">rest</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">other</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">_</span><span class="p">.</span><span class="nx">indexOf</span><span class="p">(</span><span class="nx">other</span><span class="p">,</span> <span class="nx">item</span><span class="p">)</span> <span class="o">>=</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">});</span>
<span class="p">});</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-40"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-40">¶</a> </div> <p>Zip together multiple lists into a single array -- elements that share
an index go together.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">zip</span> <span class="o">=</span> <span class="kd">function</span><span class="p">()</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">args</span> <span class="o">=</span> <span class="nx">slice</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">arguments</span><span class="p">);</span>
<span class="kd">var</span> <span class="nx">length</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">max</span><span class="p">(</span><span class="nx">_</span><span class="p">.</span><span class="nx">pluck</span><span class="p">(</span><span class="nx">args</span><span class="p">,</span> <span class="s1">'length'</span><span class="p">));</span>
<span class="kd">var</span> <span class="nx">results</span> <span class="o">=</span> <span class="k">new</span> <span class="nb">Array</span><span class="p">(</span><span class="nx">length</span><span class="p">);</span>
<span class="k">for</span> <span class="p">(</span><span class="kd">var</span> <span class="nx">i</span> <span class="o">=</span> <span class="mi">0</span><span class="p">;</span> <span class="nx">i</span> <span class="o"><</span> <span class="nx">length</span><span class="p">;</span> <span class="nx">i</span><span class="o">++</span><span class="p">)</span> <span class="nx">results</span><span class="p">[</span><span class="nx">i</span><span class="p">]</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">pluck</span><span class="p">(</span><span class="nx">args</span><span class="p">,</span> <span class="s2">""</span> <span class="o">+</span> <span class="nx">i</span><span class="p">);</span>
<span class="k">return</span> <span class="nx">results</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-41"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-41">¶</a> </div> <p>If the browser doesn't supply us with indexOf (I'm looking at you, <strong>MSIE</strong>),
we need this function. Return the position of the first occurrence of an
item in an array, or -1 if the item is not included in the array.
Delegates to <strong>ECMAScript 5</strong>'s native <code>indexOf</code> if available.
If the array is large and already in sort order, pass <code>true</code>
for <strong>isSorted</strong> to use binary search.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">indexOf</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">array</span><span class="p">,</span> <span class="nx">item</span><span class="p">,</span> <span class="nx">isSorted</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">array</span> <span class="o">==</span> <span class="kc">null</span><span class="p">)</span> <span class="k">return</span> <span class="o">-</span><span class="mi">1</span><span class="p">;</span>
<span class="kd">var</span> <span class="nx">i</span><span class="p">,</span> <span class="nx">l</span><span class="p">;</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">isSorted</span><span class="p">)</span> <span class="p">{</span>
<span class="nx">i</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">sortedIndex</span><span class="p">(</span><span class="nx">array</span><span class="p">,</span> <span class="nx">item</span><span class="p">);</span>
<span class="k">return</span> <span class="nx">array</span><span class="p">[</span><span class="nx">i</span><span class="p">]</span> <span class="o">===</span> <span class="nx">item</span> <span class="o">?</span> <span class="nx">i</span> <span class="o">:</span> <span class="o">-</span><span class="mi">1</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">nativeIndexOf</span> <span class="o">&&</span> <span class="nx">array</span><span class="p">.</span><span class="nx">indexOf</span> <span class="o">===</span> <span class="nx">nativeIndexOf</span><span class="p">)</span> <span class="k">return</span> <span class="nx">array</span><span class="p">.</span><span class="nx">indexOf</span><span class="p">(</span><span class="nx">item</span><span class="p">);</span>
<span class="k">for</span> <span class="p">(</span><span class="nx">i</span> <span class="o">=</span> <span class="mi">0</span><span class="p">,</span> <span class="nx">l</span> <span class="o">=</span> <span class="nx">array</span><span class="p">.</span><span class="nx">length</span><span class="p">;</span> <span class="nx">i</span> <span class="o"><</span> <span class="nx">l</span><span class="p">;</span> <span class="nx">i</span><span class="o">++</span><span class="p">)</span> <span class="k">if</span> <span class="p">(</span><span class="nx">array</span><span class="p">[</span><span class="nx">i</span><span class="p">]</span> <span class="o">===</span> <span class="nx">item</span><span class="p">)</span> <span class="k">return</span> <span class="nx">i</span><span class="p">;</span>
<span class="k">return</span> <span class="o">-</span><span class="mi">1</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-42"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-42">¶</a> </div> <p>Delegates to <strong>ECMAScript 5</strong>'s native <code>lastIndexOf</code> if available.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">lastIndexOf</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">array</span><span class="p">,</span> <span class="nx">item</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">array</span> <span class="o">==</span> <span class="kc">null</span><span class="p">)</span> <span class="k">return</span> <span class="o">-</span><span class="mi">1</span><span class="p">;</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">nativeLastIndexOf</span> <span class="o">&&</span> <span class="nx">array</span><span class="p">.</span><span class="nx">lastIndexOf</span> <span class="o">===</span> <span class="nx">nativeLastIndexOf</span><span class="p">)</span> <span class="k">return</span> <span class="nx">array</span><span class="p">.</span><span class="nx">lastIndexOf</span><span class="p">(</span><span class="nx">item</span><span class="p">);</span>
<span class="kd">var</span> <span class="nx">i</span> <span class="o">=</span> <span class="nx">array</span><span class="p">.</span><span class="nx">length</span><span class="p">;</span>
<span class="k">while</span> <span class="p">(</span><span class="nx">i</span><span class="o">--</span><span class="p">)</span> <span class="k">if</span> <span class="p">(</span><span class="nx">array</span><span class="p">[</span><span class="nx">i</span><span class="p">]</span> <span class="o">===</span> <span class="nx">item</span><span class="p">)</span> <span class="k">return</span> <span class="nx">i</span><span class="p">;</span>
<span class="k">return</span> <span class="o">-</span><span class="mi">1</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-43"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-43">¶</a> </div> <p>Generate an integer Array containing an arithmetic progression. A port of
the native Python <code>range()</code> function. See
<a href="http://docs.python.org/library/functions.html#range">the Python documentation</a>.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">range</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">start</span><span class="p">,</span> <span class="nx">stop</span><span class="p">,</span> <span class="nx">step</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">arguments</span><span class="p">.</span><span class="nx">length</span> <span class="o"><=</span> <span class="mi">1</span><span class="p">)</span> <span class="p">{</span>
<span class="nx">stop</span> <span class="o">=</span> <span class="nx">start</span> <span class="o">||</span> <span class="mi">0</span><span class="p">;</span>
<span class="nx">start</span> <span class="o">=</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="nx">step</span> <span class="o">=</span> <span class="nx">arguments</span><span class="p">[</span><span class="mi">2</span><span class="p">]</span> <span class="o">||</span> <span class="mi">1</span><span class="p">;</span>
<span class="kd">var</span> <span class="nx">len</span> <span class="o">=</span> <span class="nb">Math</span><span class="p">.</span><span class="nx">max</span><span class="p">(</span><span class="nb">Math</span><span class="p">.</span><span class="nx">ceil</span><span class="p">((</span><span class="nx">stop</span> <span class="o">-</span> <span class="nx">start</span><span class="p">)</span> <span class="o">/</span> <span class="nx">step</span><span class="p">),</span> <span class="mi">0</span><span class="p">);</span>
<span class="kd">var</span> <span class="nx">idx</span> <span class="o">=</span> <span class="mi">0</span><span class="p">;</span>
<span class="kd">var</span> <span class="nx">range</span> <span class="o">=</span> <span class="k">new</span> <span class="nb">Array</span><span class="p">(</span><span class="nx">len</span><span class="p">);</span>
<span class="k">while</span><span class="p">(</span><span class="nx">idx</span> <span class="o"><</span> <span class="nx">len</span><span class="p">)</span> <span class="p">{</span>
<span class="nx">range</span><span class="p">[</span><span class="nx">idx</span><span class="o">++</span><span class="p">]</span> <span class="o">=</span> <span class="nx">start</span><span class="p">;</span>
<span class="nx">start</span> <span class="o">+=</span> <span class="nx">step</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="nx">range</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-44"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-44">¶</a> </div> <h2>Function (ahem) Functions</h2> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-45"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-45">¶</a> </div> <p>Create a function bound to a given object (assigning <code>this</code>, and arguments,
optionally). Binding with arguments is also known as <code>curry</code>.
Delegates to <strong>ECMAScript 5</strong>'s native <code>Function.bind</code> if available.
We check for <code>func.bind</code> first, to fail fast when <code>func</code> is undefined.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">bind</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">func</span><span class="p">,</span> <span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">func</span><span class="p">.</span><span class="nx">bind</span> <span class="o">===</span> <span class="nx">nativeBind</span> <span class="o">&&</span> <span class="nx">nativeBind</span><span class="p">)</span> <span class="k">return</span> <span class="nx">nativeBind</span><span class="p">.</span><span class="nx">apply</span><span class="p">(</span><span class="nx">func</span><span class="p">,</span> <span class="nx">slice</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">arguments</span><span class="p">,</span> <span class="mi">1</span><span class="p">));</span>
<span class="kd">var</span> <span class="nx">args</span> <span class="o">=</span> <span class="nx">slice</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">arguments</span><span class="p">,</span> <span class="mi">2</span><span class="p">);</span>
<span class="k">return</span> <span class="kd">function</span><span class="p">()</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">func</span><span class="p">.</span><span class="nx">apply</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">args</span><span class="p">.</span><span class="nx">concat</span><span class="p">(</span><span class="nx">slice</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">arguments</span><span class="p">)));</span>
<span class="p">};</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-46"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-46">¶</a> </div> <p>Bind all of an object's methods to that object. Useful for ensuring that
all callbacks defined on an object belong to it.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">bindAll</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">funcs</span> <span class="o">=</span> <span class="nx">slice</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">arguments</span><span class="p">,</span> <span class="mi">1</span><span class="p">);</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">funcs</span><span class="p">.</span><span class="nx">length</span> <span class="o">==</span> <span class="mi">0</span><span class="p">)</span> <span class="nx">funcs</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">functions</span><span class="p">(</span><span class="nx">obj</span><span class="p">);</span>
<span class="nx">each</span><span class="p">(</span><span class="nx">funcs</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">f</span><span class="p">)</span> <span class="p">{</span> <span class="nx">obj</span><span class="p">[</span><span class="nx">f</span><span class="p">]</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">bind</span><span class="p">(</span><span class="nx">obj</span><span class="p">[</span><span class="nx">f</span><span class="p">],</span> <span class="nx">obj</span><span class="p">);</span> <span class="p">});</span>
<span class="k">return</span> <span class="nx">obj</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-47"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-47">¶</a> </div> <p>Memoize an expensive function by storing its results.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">memoize</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">func</span><span class="p">,</span> <span class="nx">hasher</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">memo</span> <span class="o">=</span> <span class="p">{};</span>
<span class="nx">hasher</span> <span class="o">||</span> <span class="p">(</span><span class="nx">hasher</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">identity</span><span class="p">);</span>
<span class="k">return</span> <span class="kd">function</span><span class="p">()</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">key</span> <span class="o">=</span> <span class="nx">hasher</span><span class="p">.</span><span class="nx">apply</span><span class="p">(</span><span class="k">this</span><span class="p">,</span> <span class="nx">arguments</span><span class="p">);</span>
<span class="k">return</span> <span class="nx">hasOwnProperty</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">memo</span><span class="p">,</span> <span class="nx">key</span><span class="p">)</span> <span class="o">?</span> <span class="nx">memo</span><span class="p">[</span><span class="nx">key</span><span class="p">]</span> <span class="o">:</span> <span class="p">(</span><span class="nx">memo</span><span class="p">[</span><span class="nx">key</span><span class="p">]</span> <span class="o">=</span> <span class="nx">func</span><span class="p">.</span><span class="nx">apply</span><span class="p">(</span><span class="k">this</span><span class="p">,</span> <span class="nx">arguments</span><span class="p">));</span>
<span class="p">};</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-48"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-48">¶</a> </div> <p>Delays a function for the given number of milliseconds, and then calls
it with the arguments supplied.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">delay</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">func</span><span class="p">,</span> <span class="nx">wait</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">args</span> <span class="o">=</span> <span class="nx">slice</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">arguments</span><span class="p">,</span> <span class="mi">2</span><span class="p">);</span>
<span class="k">return</span> <span class="nx">setTimeout</span><span class="p">(</span><span class="kd">function</span><span class="p">(){</span> <span class="k">return</span> <span class="nx">func</span><span class="p">.</span><span class="nx">apply</span><span class="p">(</span><span class="nx">func</span><span class="p">,</span> <span class="nx">args</span><span class="p">);</span> <span class="p">},</span> <span class="nx">wait</span><span class="p">);</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-49"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-49">¶</a> </div> <p>Defers a function, scheduling it to run after the current call stack has
cleared.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">defer</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">func</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">_</span><span class="p">.</span><span class="nx">delay</span><span class="p">.</span><span class="nx">apply</span><span class="p">(</span><span class="nx">_</span><span class="p">,</span> <span class="p">[</span><span class="nx">func</span><span class="p">,</span> <span class="mi">1</span><span class="p">].</span><span class="nx">concat</span><span class="p">(</span><span class="nx">slice</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">arguments</span><span class="p">,</span> <span class="mi">1</span><span class="p">)));</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-50"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-50">¶</a> </div> <p>Internal function used to implement <code>_.throttle</code> and <code>_.debounce</code>.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">limit</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">func</span><span class="p">,</span> <span class="nx">wait</span><span class="p">,</span> <span class="nx">debounce</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">timeout</span><span class="p">;</span>
<span class="k">return</span> <span class="kd">function</span><span class="p">()</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">context</span> <span class="o">=</span> <span class="k">this</span><span class="p">,</span> <span class="nx">args</span> <span class="o">=</span> <span class="nx">arguments</span><span class="p">;</span>
<span class="kd">var</span> <span class="nx">throttler</span> <span class="o">=</span> <span class="kd">function</span><span class="p">()</span> <span class="p">{</span>
<span class="nx">timeout</span> <span class="o">=</span> <span class="kc">null</span><span class="p">;</span>
<span class="nx">func</span><span class="p">.</span><span class="nx">apply</span><span class="p">(</span><span class="nx">context</span><span class="p">,</span> <span class="nx">args</span><span class="p">);</span>
<span class="p">};</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">debounce</span><span class="p">)</span> <span class="nx">clearTimeout</span><span class="p">(</span><span class="nx">timeout</span><span class="p">);</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">debounce</span> <span class="o">||</span> <span class="o">!</span><span class="nx">timeout</span><span class="p">)</span> <span class="nx">timeout</span> <span class="o">=</span> <span class="nx">setTimeout</span><span class="p">(</span><span class="nx">throttler</span><span class="p">,</span> <span class="nx">wait</span><span class="p">);</span>
<span class="p">};</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-51"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-51">¶</a> </div> <p>Returns a function, that, when invoked, will only be triggered at most once
during a given window of time.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">throttle</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">func</span><span class="p">,</span> <span class="nx">wait</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">limit</span><span class="p">(</span><span class="nx">func</span><span class="p">,</span> <span class="nx">wait</span><span class="p">,</span> <span class="kc">false</span><span class="p">);</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-52"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-52">¶</a> </div> <p>Returns a function, that, as long as it continues to be invoked, will not
be triggered. The function will be called after it stops being called for
N milliseconds.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">debounce</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">func</span><span class="p">,</span> <span class="nx">wait</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">limit</span><span class="p">(</span><span class="nx">func</span><span class="p">,</span> <span class="nx">wait</span><span class="p">,</span> <span class="kc">true</span><span class="p">);</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-53"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-53">¶</a> </div> <p>Returns a function that will be executed at most one time, no matter how
often you call it. Useful for lazy initialization.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">once</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">func</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">ran</span> <span class="o">=</span> <span class="kc">false</span><span class="p">,</span> <span class="nx">memo</span><span class="p">;</span>
<span class="k">return</span> <span class="kd">function</span><span class="p">()</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">ran</span><span class="p">)</span> <span class="k">return</span> <span class="nx">memo</span><span class="p">;</span>
<span class="nx">ran</span> <span class="o">=</span> <span class="kc">true</span><span class="p">;</span>
<span class="k">return</span> <span class="nx">memo</span> <span class="o">=</span> <span class="nx">func</span><span class="p">.</span><span class="nx">apply</span><span class="p">(</span><span class="k">this</span><span class="p">,</span> <span class="nx">arguments</span><span class="p">);</span>
<span class="p">};</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-54"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-54">¶</a> </div> <p>Returns the first function passed as an argument to the second,
allowing you to adjust arguments, run code before and after, and
conditionally execute the original function.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">wrap</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">func</span><span class="p">,</span> <span class="nx">wrapper</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="kd">function</span><span class="p">()</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">args</span> <span class="o">=</span> <span class="p">[</span><span class="nx">func</span><span class="p">].</span><span class="nx">concat</span><span class="p">(</span><span class="nx">slice</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">arguments</span><span class="p">));</span>
<span class="k">return</span> <span class="nx">wrapper</span><span class="p">.</span><span class="nx">apply</span><span class="p">(</span><span class="k">this</span><span class="p">,</span> <span class="nx">args</span><span class="p">);</span>
<span class="p">};</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-55"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-55">¶</a> </div> <p>Returns a function that is the composition of a list of functions, each
consuming the return value of the function that follows.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">compose</span> <span class="o">=</span> <span class="kd">function</span><span class="p">()</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">funcs</span> <span class="o">=</span> <span class="nx">slice</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">arguments</span><span class="p">);</span>
<span class="k">return</span> <span class="kd">function</span><span class="p">()</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">args</span> <span class="o">=</span> <span class="nx">slice</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">arguments</span><span class="p">);</span>
<span class="k">for</span> <span class="p">(</span><span class="kd">var</span> <span class="nx">i</span><span class="o">=</span><span class="nx">funcs</span><span class="p">.</span><span class="nx">length</span><span class="o">-</span><span class="mi">1</span><span class="p">;</span> <span class="nx">i</span> <span class="o">>=</span> <span class="mi">0</span><span class="p">;</span> <span class="nx">i</span><span class="o">--</span><span class="p">)</span> <span class="p">{</span>
<span class="nx">args</span> <span class="o">=</span> <span class="p">[</span><span class="nx">funcs</span><span class="p">[</span><span class="nx">i</span><span class="p">].</span><span class="nx">apply</span><span class="p">(</span><span class="k">this</span><span class="p">,</span> <span class="nx">args</span><span class="p">)];</span>
<span class="p">}</span>
<span class="k">return</span> <span class="nx">args</span><span class="p">[</span><span class="mi">0</span><span class="p">];</span>
<span class="p">};</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-56"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-56">¶</a> </div> <p>Returns a function that will only be executed after being called N times.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">after</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">times</span><span class="p">,</span> <span class="nx">func</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="kd">function</span><span class="p">()</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="o">--</span><span class="nx">times</span> <span class="o"><</span> <span class="mi">1</span><span class="p">)</span> <span class="p">{</span> <span class="k">return</span> <span class="nx">func</span><span class="p">.</span><span class="nx">apply</span><span class="p">(</span><span class="k">this</span><span class="p">,</span> <span class="nx">arguments</span><span class="p">);</span> <span class="p">}</span>
<span class="p">};</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-57"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-57">¶</a> </div> <h2>Object Functions</h2> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-58"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-58">¶</a> </div> <p>Retrieve the names of an object's properties.
Delegates to <strong>ECMAScript 5</strong>'s native <code>Object.keys</code></p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">keys</span> <span class="o">=</span> <span class="nx">nativeKeys</span> <span class="o">||</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">obj</span> <span class="o">!==</span> <span class="nb">Object</span><span class="p">(</span><span class="nx">obj</span><span class="p">))</span> <span class="k">throw</span> <span class="k">new</span> <span class="nx">TypeError</span><span class="p">(</span><span class="s1">'Invalid object'</span><span class="p">);</span>
<span class="kd">var</span> <span class="nx">keys</span> <span class="o">=</span> <span class="p">[];</span>
<span class="k">for</span> <span class="p">(</span><span class="kd">var</span> <span class="nx">key</span> <span class="k">in</span> <span class="nx">obj</span><span class="p">)</span> <span class="k">if</span> <span class="p">(</span><span class="nx">hasOwnProperty</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">key</span><span class="p">))</span> <span class="nx">keys</span><span class="p">[</span><span class="nx">keys</span><span class="p">.</span><span class="nx">length</span><span class="p">]</span> <span class="o">=</span> <span class="nx">key</span><span class="p">;</span>
<span class="k">return</span> <span class="nx">keys</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-59"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-59">¶</a> </div> <p>Retrieve the values of an object's properties.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">values</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">_</span><span class="p">.</span><span class="nx">map</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">_</span><span class="p">.</span><span class="nx">identity</span><span class="p">);</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-60"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-60">¶</a> </div> <p>Return a sorted list of the function names available on the object.
Aliased as <code>methods</code></p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">functions</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">methods</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">_</span><span class="p">.</span><span class="nx">filter</span><span class="p">(</span><span class="nx">_</span><span class="p">.</span><span class="nx">keys</span><span class="p">(</span><span class="nx">obj</span><span class="p">),</span> <span class="kd">function</span><span class="p">(</span><span class="nx">key</span><span class="p">){</span> <span class="k">return</span> <span class="nx">_</span><span class="p">.</span><span class="nx">isFunction</span><span class="p">(</span><span class="nx">obj</span><span class="p">[</span><span class="nx">key</span><span class="p">]);</span> <span class="p">}).</span><span class="nx">sort</span><span class="p">();</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-61"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-61">¶</a> </div> <p>Extend a given object with all the properties in passed-in object(s).</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">extend</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="nx">each</span><span class="p">(</span><span class="nx">slice</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">arguments</span><span class="p">,</span> <span class="mi">1</span><span class="p">),</span> <span class="kd">function</span><span class="p">(</span><span class="nx">source</span><span class="p">)</span> <span class="p">{</span>
<span class="k">for</span> <span class="p">(</span><span class="kd">var</span> <span class="nx">prop</span> <span class="k">in</span> <span class="nx">source</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">source</span><span class="p">[</span><span class="nx">prop</span><span class="p">]</span> <span class="o">!==</span> <span class="k">void</span> <span class="mi">0</span><span class="p">)</span> <span class="nx">obj</span><span class="p">[</span><span class="nx">prop</span><span class="p">]</span> <span class="o">=</span> <span class="nx">source</span><span class="p">[</span><span class="nx">prop</span><span class="p">];</span>
<span class="p">}</span>
<span class="p">});</span>
<span class="k">return</span> <span class="nx">obj</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-62"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-62">¶</a> </div> <p>Fill in a given object with default properties.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">defaults</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="nx">each</span><span class="p">(</span><span class="nx">slice</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">arguments</span><span class="p">,</span> <span class="mi">1</span><span class="p">),</span> <span class="kd">function</span><span class="p">(</span><span class="nx">source</span><span class="p">)</span> <span class="p">{</span>
<span class="k">for</span> <span class="p">(</span><span class="kd">var</span> <span class="nx">prop</span> <span class="k">in</span> <span class="nx">source</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">obj</span><span class="p">[</span><span class="nx">prop</span><span class="p">]</span> <span class="o">==</span> <span class="kc">null</span><span class="p">)</span> <span class="nx">obj</span><span class="p">[</span><span class="nx">prop</span><span class="p">]</span> <span class="o">=</span> <span class="nx">source</span><span class="p">[</span><span class="nx">prop</span><span class="p">];</span>
<span class="p">}</span>
<span class="p">});</span>
<span class="k">return</span> <span class="nx">obj</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-63"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-63">¶</a> </div> <p>Create a (shallow-cloned) duplicate of an object.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">clone</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">_</span><span class="p">.</span><span class="nx">isArray</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="o">?</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">slice</span><span class="p">()</span> <span class="o">:</span> <span class="nx">_</span><span class="p">.</span><span class="nx">extend</span><span class="p">({},</span> <span class="nx">obj</span><span class="p">);</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-64"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-64">¶</a> </div> <p>Invokes interceptor with the obj, and then returns obj.
The primary purpose of this method is to "tap into" a method chain, in
order to perform operations on intermediate results within the chain.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">tap</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">interceptor</span><span class="p">)</span> <span class="p">{</span>
<span class="nx">interceptor</span><span class="p">(</span><span class="nx">obj</span><span class="p">);</span>
<span class="k">return</span> <span class="nx">obj</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-65"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-65">¶</a> </div> <p>Perform a deep comparison to check if two objects are equal.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">isEqual</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">a</span><span class="p">,</span> <span class="nx">b</span><span class="p">)</span> <span class="p">{</span></pre></div> </td> </tr> <tr id="section-66"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-66">¶</a> </div> <p>Check object identity.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="k">if</span> <span class="p">(</span><span class="nx">a</span> <span class="o">===</span> <span class="nx">b</span><span class="p">)</span> <span class="k">return</span> <span class="kc">true</span><span class="p">;</span></pre></div> </td> </tr> <tr id="section-67"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-67">¶</a> </div> <p>Different types?</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">atype</span> <span class="o">=</span> <span class="k">typeof</span><span class="p">(</span><span class="nx">a</span><span class="p">),</span> <span class="nx">btype</span> <span class="o">=</span> <span class="k">typeof</span><span class="p">(</span><span class="nx">b</span><span class="p">);</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">atype</span> <span class="o">!=</span> <span class="nx">btype</span><span class="p">)</span> <span class="k">return</span> <span class="kc">false</span><span class="p">;</span></pre></div> </td> </tr> <tr id="section-68"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-68">¶</a> </div> <p>Basic equality test (watch out for coercions).</p> </td> <td class="code"> <div class="highlight"><pre> <span class="k">if</span> <span class="p">(</span><span class="nx">a</span> <span class="o">==</span> <span class="nx">b</span><span class="p">)</span> <span class="k">return</span> <span class="kc">true</span><span class="p">;</span></pre></div> </td> </tr> <tr id="section-69"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-69">¶</a> </div> <p>One is falsy and the other truthy.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="k">if</span> <span class="p">((</span><span class="o">!</span><span class="nx">a</span> <span class="o">&&</span> <span class="nx">b</span><span class="p">)</span> <span class="o">||</span> <span class="p">(</span><span class="nx">a</span> <span class="o">&&</span> <span class="o">!</span><span class="nx">b</span><span class="p">))</span> <span class="k">return</span> <span class="kc">false</span><span class="p">;</span></pre></div> </td> </tr> <tr id="section-70"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-70">¶</a> </div> <p>Unwrap any wrapped objects.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="k">if</span> <span class="p">(</span><span class="nx">a</span><span class="p">.</span><span class="nx">_chain</span><span class="p">)</span> <span class="nx">a</span> <span class="o">=</span> <span class="nx">a</span><span class="p">.</span><span class="nx">_wrapped</span><span class="p">;</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">b</span><span class="p">.</span><span class="nx">_chain</span><span class="p">)</span> <span class="nx">b</span> <span class="o">=</span> <span class="nx">b</span><span class="p">.</span><span class="nx">_wrapped</span><span class="p">;</span></pre></div> </td> </tr> <tr id="section-71"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-71">¶</a> </div> <p>One of them implements an isEqual()?</p> </td> <td class="code"> <div class="highlight"><pre> <span class="k">if</span> <span class="p">(</span><span class="nx">a</span><span class="p">.</span><span class="nx">isEqual</span><span class="p">)</span> <span class="k">return</span> <span class="nx">a</span><span class="p">.</span><span class="nx">isEqual</span><span class="p">(</span><span class="nx">b</span><span class="p">);</span></pre></div> </td> </tr> <tr id="section-72"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-72">¶</a> </div> <p>Check dates' integer values.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="k">if</span> <span class="p">(</span><span class="nx">_</span><span class="p">.</span><span class="nx">isDate</span><span class="p">(</span><span class="nx">a</span><span class="p">)</span> <span class="o">&&</span> <span class="nx">_</span><span class="p">.</span><span class="nx">isDate</span><span class="p">(</span><span class="nx">b</span><span class="p">))</span> <span class="k">return</span> <span class="nx">a</span><span class="p">.</span><span class="nx">getTime</span><span class="p">()</span> <span class="o">===</span> <span class="nx">b</span><span class="p">.</span><span class="nx">getTime</span><span class="p">();</span></pre></div> </td> </tr> <tr id="section-73"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-73">¶</a> </div> <p>Both are NaN?</p> </td> <td class="code"> <div class="highlight"><pre> <span class="k">if</span> <span class="p">(</span><span class="nx">_</span><span class="p">.</span><span class="nb">isNaN</span><span class="p">(</span><span class="nx">a</span><span class="p">)</span> <span class="o">&&</span> <span class="nx">_</span><span class="p">.</span><span class="nb">isNaN</span><span class="p">(</span><span class="nx">b</span><span class="p">))</span> <span class="k">return</span> <span class="kc">false</span><span class="p">;</span></pre></div> </td> </tr> <tr id="section-74"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-74">¶</a> </div> <p>Compare regular expressions.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="k">if</span> <span class="p">(</span><span class="nx">_</span><span class="p">.</span><span class="nx">isRegExp</span><span class="p">(</span><span class="nx">a</span><span class="p">)</span> <span class="o">&&</span> <span class="nx">_</span><span class="p">.</span><span class="nx">isRegExp</span><span class="p">(</span><span class="nx">b</span><span class="p">))</span>
<span class="k">return</span> <span class="nx">a</span><span class="p">.</span><span class="nx">source</span> <span class="o">===</span> <span class="nx">b</span><span class="p">.</span><span class="nx">source</span> <span class="o">&&</span>
<span class="nx">a</span><span class="p">.</span><span class="nx">global</span> <span class="o">===</span> <span class="nx">b</span><span class="p">.</span><span class="nx">global</span> <span class="o">&&</span>
<span class="nx">a</span><span class="p">.</span><span class="nx">ignoreCase</span> <span class="o">===</span> <span class="nx">b</span><span class="p">.</span><span class="nx">ignoreCase</span> <span class="o">&&</span>
<span class="nx">a</span><span class="p">.</span><span class="nx">multiline</span> <span class="o">===</span> <span class="nx">b</span><span class="p">.</span><span class="nx">multiline</span><span class="p">;</span></pre></div> </td> </tr> <tr id="section-75"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-75">¶</a> </div> <p>If a is not an object by this point, we can't handle it.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="k">if</span> <span class="p">(</span><span class="nx">atype</span> <span class="o">!==</span> <span class="s1">'object'</span><span class="p">)</span> <span class="k">return</span> <span class="kc">false</span><span class="p">;</span></pre></div> </td> </tr> <tr id="section-76"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-76">¶</a> </div> <p>Check for different array lengths before comparing contents.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="k">if</span> <span class="p">(</span><span class="nx">a</span><span class="p">.</span><span class="nx">length</span> <span class="o">&&</span> <span class="p">(</span><span class="nx">a</span><span class="p">.</span><span class="nx">length</span> <span class="o">!==</span> <span class="nx">b</span><span class="p">.</span><span class="nx">length</span><span class="p">))</span> <span class="k">return</span> <span class="kc">false</span><span class="p">;</span></pre></div> </td> </tr> <tr id="section-77"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-77">¶</a> </div> <p>Nothing else worked, deep compare the contents.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">aKeys</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">keys</span><span class="p">(</span><span class="nx">a</span><span class="p">),</span> <span class="nx">bKeys</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">keys</span><span class="p">(</span><span class="nx">b</span><span class="p">);</span></pre></div> </td> </tr> <tr id="section-78"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-78">¶</a> </div> <p>Different object sizes?</p> </td> <td class="code"> <div class="highlight"><pre> <span class="k">if</span> <span class="p">(</span><span class="nx">aKeys</span><span class="p">.</span><span class="nx">length</span> <span class="o">!=</span> <span class="nx">bKeys</span><span class="p">.</span><span class="nx">length</span><span class="p">)</span> <span class="k">return</span> <span class="kc">false</span><span class="p">;</span></pre></div> </td> </tr> <tr id="section-79"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-79">¶</a> </div> <p>Recursive comparison of contents.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="k">for</span> <span class="p">(</span><span class="kd">var</span> <span class="nx">key</span> <span class="k">in</span> <span class="nx">a</span><span class="p">)</span> <span class="k">if</span> <span class="p">(</span><span class="o">!</span><span class="p">(</span><span class="nx">key</span> <span class="k">in</span> <span class="nx">b</span><span class="p">)</span> <span class="o">||</span> <span class="o">!</span><span class="nx">_</span><span class="p">.</span><span class="nx">isEqual</span><span class="p">(</span><span class="nx">a</span><span class="p">[</span><span class="nx">key</span><span class="p">],</span> <span class="nx">b</span><span class="p">[</span><span class="nx">key</span><span class="p">]))</span> <span class="k">return</span> <span class="kc">false</span><span class="p">;</span>
<span class="k">return</span> <span class="kc">true</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-80"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-80">¶</a> </div> <p>Is a given array or object empty?</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">isEmpty</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">_</span><span class="p">.</span><span class="nx">isArray</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="o">||</span> <span class="nx">_</span><span class="p">.</span><span class="nx">isString</span><span class="p">(</span><span class="nx">obj</span><span class="p">))</span> <span class="k">return</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">length</span> <span class="o">===</span> <span class="mi">0</span><span class="p">;</span>
<span class="k">for</span> <span class="p">(</span><span class="kd">var</span> <span class="nx">key</span> <span class="k">in</span> <span class="nx">obj</span><span class="p">)</span> <span class="k">if</span> <span class="p">(</span><span class="nx">hasOwnProperty</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">key</span><span class="p">))</span> <span class="k">return</span> <span class="kc">false</span><span class="p">;</span>
<span class="k">return</span> <span class="kc">true</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-81"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-81">¶</a> </div> <p>Is a given value a DOM element?</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">isElement</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="o">!!</span><span class="p">(</span><span class="nx">obj</span> <span class="o">&&</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">nodeType</span> <span class="o">==</span> <span class="mi">1</span><span class="p">);</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-82"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-82">¶</a> </div> <p>Is a given value an array?
Delegates to ECMA5's native Array.isArray</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">isArray</span> <span class="o">=</span> <span class="nx">nativeIsArray</span> <span class="o">||</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">toString</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="o">===</span> <span class="s1">'[object Array]'</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-83"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-83">¶</a> </div> <p>Is a given variable an arguments object?</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">isArguments</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="o">!!</span><span class="p">(</span><span class="nx">obj</span> <span class="o">&&</span> <span class="nx">hasOwnProperty</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="s1">'callee'</span><span class="p">));</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-84"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-84">¶</a> </div> <p>Is a given value a function?</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">isFunction</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="o">!!</span><span class="p">(</span><span class="nx">obj</span> <span class="o">&&</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">constructor</span> <span class="o">&&</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">call</span> <span class="o">&&</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">apply</span><span class="p">);</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-85"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-85">¶</a> </div> <p>Is a given value a string?</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">isString</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="o">!!</span><span class="p">(</span><span class="nx">obj</span> <span class="o">===</span> <span class="s1">''</span> <span class="o">||</span> <span class="p">(</span><span class="nx">obj</span> <span class="o">&&</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">charCodeAt</span> <span class="o">&&</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">substr</span><span class="p">));</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-86"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-86">¶</a> </div> <p>Is a given value a number?</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">isNumber</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="o">!!</span><span class="p">(</span><span class="nx">obj</span> <span class="o">===</span> <span class="mi">0</span> <span class="o">||</span> <span class="p">(</span><span class="nx">obj</span> <span class="o">&&</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">toExponential</span> <span class="o">&&</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">toFixed</span><span class="p">));</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-87"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-87">¶</a> </div> <p>Is the given value <code>NaN</code>? <code>NaN</code> happens to be the only value in JavaScript
that does not equal itself.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nb">isNaN</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">obj</span> <span class="o">!==</span> <span class="nx">obj</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-88"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-88">¶</a> </div> <p>Is a given value a boolean?</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">isBoolean</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">obj</span> <span class="o">===</span> <span class="kc">true</span> <span class="o">||</span> <span class="nx">obj</span> <span class="o">===</span> <span class="kc">false</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-89"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-89">¶</a> </div> <p>Is a given value a date?</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">isDate</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="o">!!</span><span class="p">(</span><span class="nx">obj</span> <span class="o">&&</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">getTimezoneOffset</span> <span class="o">&&</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">setUTCFullYear</span><span class="p">);</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-90"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-90">¶</a> </div> <p>Is the given value a regular expression?</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">isRegExp</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="o">!!</span><span class="p">(</span><span class="nx">obj</span> <span class="o">&&</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">test</span> <span class="o">&&</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">exec</span> <span class="o">&&</span> <span class="p">(</span><span class="nx">obj</span><span class="p">.</span><span class="nx">ignoreCase</span> <span class="o">||</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">ignoreCase</span> <span class="o">===</span> <span class="kc">false</span><span class="p">));</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-91"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-91">¶</a> </div> <p>Is a given value equal to null?</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">isNull</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">obj</span> <span class="o">===</span> <span class="kc">null</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-92"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-92">¶</a> </div> <p>Is a given variable undefined?</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">isUndefined</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">obj</span> <span class="o">===</span> <span class="k">void</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-93"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-93">¶</a> </div> <h2>Utility Functions</h2> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-94"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-94">¶</a> </div> <p>Run Underscore.js in <em>noConflict</em> mode, returning the <code>_</code> variable to its
previous owner. Returns a reference to the Underscore object.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">noConflict</span> <span class="o">=</span> <span class="kd">function</span><span class="p">()</span> <span class="p">{</span>
<span class="nx">root</span><span class="p">.</span><span class="nx">_</span> <span class="o">=</span> <span class="nx">previousUnderscore</span><span class="p">;</span>
<span class="k">return</span> <span class="k">this</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-95"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-95">¶</a> </div> <p>Keep the identity function around for default iterators.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">identity</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">value</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">value</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-96"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-96">¶</a> </div> <p>Run a function <strong>n</strong> times.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">times</span> <span class="o">=</span> <span class="kd">function</span> <span class="p">(</span><span class="nx">n</span><span class="p">,</span> <span class="nx">iterator</span><span class="p">,</span> <span class="nx">context</span><span class="p">)</span> <span class="p">{</span>
<span class="k">for</span> <span class="p">(</span><span class="kd">var</span> <span class="nx">i</span> <span class="o">=</span> <span class="mi">0</span><span class="p">;</span> <span class="nx">i</span> <span class="o"><</span> <span class="nx">n</span><span class="p">;</span> <span class="nx">i</span><span class="o">++</span><span class="p">)</span> <span class="nx">iterator</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">context</span><span class="p">,</span> <span class="nx">i</span><span class="p">);</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-97"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-97">¶</a> </div> <p>Add your own custom functions to the Underscore object, ensuring that
they're correctly added to the OOP wrapper as well.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">mixin</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span>
<span class="nx">each</span><span class="p">(</span><span class="nx">_</span><span class="p">.</span><span class="nx">functions</span><span class="p">(</span><span class="nx">obj</span><span class="p">),</span> <span class="kd">function</span><span class="p">(</span><span class="nx">name</span><span class="p">){</span>
<span class="nx">addToWrapper</span><span class="p">(</span><span class="nx">name</span><span class="p">,</span> <span class="nx">_</span><span class="p">[</span><span class="nx">name</span><span class="p">]</span> <span class="o">=</span> <span class="nx">obj</span><span class="p">[</span><span class="nx">name</span><span class="p">]);</span>
<span class="p">});</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-98"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-98">¶</a> </div> <p>Generate a unique integer id (unique within the entire client session).
Useful for temporary DOM ids.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">idCounter</span> <span class="o">=</span> <span class="mi">0</span><span class="p">;</span>
<span class="nx">_</span><span class="p">.</span><span class="nx">uniqueId</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">prefix</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">id</span> <span class="o">=</span> <span class="nx">idCounter</span><span class="o">++</span><span class="p">;</span>
<span class="k">return</span> <span class="nx">prefix</span> <span class="o">?</span> <span class="nx">prefix</span> <span class="o">+</span> <span class="nx">id</span> <span class="o">:</span> <span class="nx">id</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-99"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-99">¶</a> </div> <p>By default, Underscore uses ERB-style template delimiters, change the
following template settings to use alternative delimiters.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">templateSettings</span> <span class="o">=</span> <span class="p">{</span>
<span class="nx">evaluate</span> <span class="o">:</span> <span class="sr">/<%([\s\S]+?)%>/g</span><span class="p">,</span>
<span class="nx">interpolate</span> <span class="o">:</span> <span class="sr">/<%=([\s\S]+?)%>/g</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-100"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-100">¶</a> </div> <p>JavaScript micro-templating, similar to John Resig's implementation.
Underscore templating handles arbitrary delimiters, preserves whitespace,
and correctly escapes quotes within interpolated code.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">template</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">str</span><span class="p">,</span> <span class="nx">data</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">c</span> <span class="o">=</span> <span class="nx">_</span><span class="p">.</span><span class="nx">templateSettings</span><span class="p">;</span>
<span class="kd">var</span> <span class="nx">tmpl</span> <span class="o">=</span> <span class="s1">'var __p=[],print=function(){__p.push.apply(__p,arguments);};'</span> <span class="o">+</span>
<span class="s1">'with(obj||{}){__p.push(\''</span> <span class="o">+</span>
<span class="nx">str</span><span class="p">.</span><span class="nx">replace</span><span class="p">(</span><span class="sr">/\\/g</span><span class="p">,</span> <span class="s1">'\\\\'</span><span class="p">)</span>
<span class="p">.</span><span class="nx">replace</span><span class="p">(</span><span class="sr">/'/g</span><span class="p">,</span> <span class="s2">"\\'"</span><span class="p">)</span>
<span class="p">.</span><span class="nx">replace</span><span class="p">(</span><span class="nx">c</span><span class="p">.</span><span class="nx">interpolate</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">match</span><span class="p">,</span> <span class="nx">code</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="s2">"',"</span> <span class="o">+</span> <span class="nx">code</span><span class="p">.</span><span class="nx">replace</span><span class="p">(</span><span class="sr">/\\'/g</span><span class="p">,</span> <span class="s2">"'"</span><span class="p">)</span> <span class="o">+</span> <span class="s2">",'"</span><span class="p">;</span>
<span class="p">})</span>
<span class="p">.</span><span class="nx">replace</span><span class="p">(</span><span class="nx">c</span><span class="p">.</span><span class="nx">evaluate</span> <span class="o">||</span> <span class="kc">null</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">match</span><span class="p">,</span> <span class="nx">code</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="s2">"');"</span> <span class="o">+</span> <span class="nx">code</span><span class="p">.</span><span class="nx">replace</span><span class="p">(</span><span class="sr">/\\'/g</span><span class="p">,</span> <span class="s2">"'"</span><span class="p">)</span>
<span class="p">.</span><span class="nx">replace</span><span class="p">(</span><span class="sr">/[\r\n\t]/g</span><span class="p">,</span> <span class="s1">' '</span><span class="p">)</span> <span class="o">+</span> <span class="s2">"__p.push('"</span><span class="p">;</span>
<span class="p">})</span>
<span class="p">.</span><span class="nx">replace</span><span class="p">(</span><span class="sr">/\r/g</span><span class="p">,</span> <span class="s1">'\\r'</span><span class="p">)</span>
<span class="p">.</span><span class="nx">replace</span><span class="p">(</span><span class="sr">/\n/g</span><span class="p">,</span> <span class="s1">'\\n'</span><span class="p">)</span>
<span class="p">.</span><span class="nx">replace</span><span class="p">(</span><span class="sr">/\t/g</span><span class="p">,</span> <span class="s1">'\\t'</span><span class="p">)</span>
<span class="o">+</span> <span class="s2">"');}return __p.join('');"</span><span class="p">;</span>
<span class="kd">var</span> <span class="nx">func</span> <span class="o">=</span> <span class="k">new</span> <span class="nb">Function</span><span class="p">(</span><span class="s1">'obj'</span><span class="p">,</span> <span class="nx">tmpl</span><span class="p">);</span>
<span class="k">return</span> <span class="nx">data</span> <span class="o">?</span> <span class="nx">func</span><span class="p">(</span><span class="nx">data</span><span class="p">)</span> <span class="o">:</span> <span class="nx">func</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-101"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-101">¶</a> </div> <h2>The OOP Wrapper</h2> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-102"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-102">¶</a> </div> <p>If Underscore is called as a function, it returns a wrapped object that
can be used OO-style. This wrapper holds altered versions of all the
underscore functions. Wrapped objects may be chained.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">wrapper</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">)</span> <span class="p">{</span> <span class="k">this</span><span class="p">.</span><span class="nx">_wrapped</span> <span class="o">=</span> <span class="nx">obj</span><span class="p">;</span> <span class="p">};</span></pre></div> </td> </tr> <tr id="section-103"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-103">¶</a> </div> <p>Expose <code>wrapper.prototype</code> as <code>_.prototype</code></p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">prototype</span> <span class="o">=</span> <span class="nx">wrapper</span><span class="p">.</span><span class="nx">prototype</span><span class="p">;</span></pre></div> </td> </tr> <tr id="section-104"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-104">¶</a> </div> <p>Helper function to continue chaining intermediate results.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">result</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">chain</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">chain</span> <span class="o">?</span> <span class="nx">_</span><span class="p">(</span><span class="nx">obj</span><span class="p">).</span><span class="nx">chain</span><span class="p">()</span> <span class="o">:</span> <span class="nx">obj</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-105"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-105">¶</a> </div> <p>A method to easily add functions to the OOP wrapper.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">addToWrapper</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">name</span><span class="p">,</span> <span class="nx">func</span><span class="p">)</span> <span class="p">{</span>
<span class="nx">wrapper</span><span class="p">.</span><span class="nx">prototype</span><span class="p">[</span><span class="nx">name</span><span class="p">]</span> <span class="o">=</span> <span class="kd">function</span><span class="p">()</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">args</span> <span class="o">=</span> <span class="nx">slice</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">arguments</span><span class="p">);</span>
<span class="nx">unshift</span><span class="p">.</span><span class="nx">call</span><span class="p">(</span><span class="nx">args</span><span class="p">,</span> <span class="k">this</span><span class="p">.</span><span class="nx">_wrapped</span><span class="p">);</span>
<span class="k">return</span> <span class="nx">result</span><span class="p">(</span><span class="nx">func</span><span class="p">.</span><span class="nx">apply</span><span class="p">(</span><span class="nx">_</span><span class="p">,</span> <span class="nx">args</span><span class="p">),</span> <span class="k">this</span><span class="p">.</span><span class="nx">_chain</span><span class="p">);</span>
<span class="p">};</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-106"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-106">¶</a> </div> <p>Add all of the Underscore functions to the wrapper object.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">_</span><span class="p">.</span><span class="nx">mixin</span><span class="p">(</span><span class="nx">_</span><span class="p">);</span></pre></div> </td> </tr> <tr id="section-107"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-107">¶</a> </div> <p>Add all mutator Array functions to the wrapper.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">each</span><span class="p">([</span><span class="s1">'pop'</span><span class="p">,</span> <span class="s1">'push'</span><span class="p">,</span> <span class="s1">'reverse'</span><span class="p">,</span> <span class="s1">'shift'</span><span class="p">,</span> <span class="s1">'sort'</span><span class="p">,</span> <span class="s1">'splice'</span><span class="p">,</span> <span class="s1">'unshift'</span><span class="p">],</span> <span class="kd">function</span><span class="p">(</span><span class="nx">name</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">method</span> <span class="o">=</span> <span class="nx">ArrayProto</span><span class="p">[</span><span class="nx">name</span><span class="p">];</span>
<span class="nx">wrapper</span><span class="p">.</span><span class="nx">prototype</span><span class="p">[</span><span class="nx">name</span><span class="p">]</span> <span class="o">=</span> <span class="kd">function</span><span class="p">()</span> <span class="p">{</span>
<span class="nx">method</span><span class="p">.</span><span class="nx">apply</span><span class="p">(</span><span class="k">this</span><span class="p">.</span><span class="nx">_wrapped</span><span class="p">,</span> <span class="nx">arguments</span><span class="p">);</span>
<span class="k">return</span> <span class="nx">result</span><span class="p">(</span><span class="k">this</span><span class="p">.</span><span class="nx">_wrapped</span><span class="p">,</span> <span class="k">this</span><span class="p">.</span><span class="nx">_chain</span><span class="p">);</span>
<span class="p">};</span>
<span class="p">});</span></pre></div> </td> </tr> <tr id="section-108"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-108">¶</a> </div> <p>Add all accessor Array functions to the wrapper.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">each</span><span class="p">([</span><span class="s1">'concat'</span><span class="p">,</span> <span class="s1">'join'</span><span class="p">,</span> <span class="s1">'slice'</span><span class="p">],</span> <span class="kd">function</span><span class="p">(</span><span class="nx">name</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">method</span> <span class="o">=</span> <span class="nx">ArrayProto</span><span class="p">[</span><span class="nx">name</span><span class="p">];</span>
<span class="nx">wrapper</span><span class="p">.</span><span class="nx">prototype</span><span class="p">[</span><span class="nx">name</span><span class="p">]</span> <span class="o">=</span> <span class="kd">function</span><span class="p">()</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">result</span><span class="p">(</span><span class="nx">method</span><span class="p">.</span><span class="nx">apply</span><span class="p">(</span><span class="k">this</span><span class="p">.</span><span class="nx">_wrapped</span><span class="p">,</span> <span class="nx">arguments</span><span class="p">),</span> <span class="k">this</span><span class="p">.</span><span class="nx">_chain</span><span class="p">);</span>
<span class="p">};</span>
<span class="p">});</span></pre></div> </td> </tr> <tr id="section-109"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-109">¶</a> </div> <p>Start chaining a wrapped Underscore object.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">wrapper</span><span class="p">.</span><span class="nx">prototype</span><span class="p">.</span><span class="nx">chain</span> <span class="o">=</span> <span class="kd">function</span><span class="p">()</span> <span class="p">{</span>
<span class="k">this</span><span class="p">.</span><span class="nx">_chain</span> <span class="o">=</span> <span class="kc">true</span><span class="p">;</span>
<span class="k">return</span> <span class="k">this</span><span class="p">;</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-110"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-110">¶</a> </div> <p>Extracts the result from a wrapped and chained object.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nx">wrapper</span><span class="p">.</span><span class="nx">prototype</span><span class="p">.</span><span class="nx">value</span> <span class="o">=</span> <span class="kd">function</span><span class="p">()</span> <span class="p">{</span>
<span class="k">return</span> <span class="k">this</span><span class="p">.</span><span class="nx">_wrapped</span><span class="p">;</span>
<span class="p">};</span>
<span class="p">})();</span>
</pre></div> </td> </tr> </tbody> </table> </div> </body> </html>
|
