-
Notifications
You must be signed in to change notification settings - Fork 1
Expand file tree
/
Copy pathop_constructor.html
More file actions
485 lines (401 loc) · 45.7 KB
/
Copy pathop_constructor.html
File metadata and controls
485 lines (401 loc) · 45.7 KB
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
<!doctype html>
<html class="cpprefjp" lang="ja" itemscope="" itemtype="http://schema.org/WebPage">
<head>
<!-- Google tag (gtag.js) -->
<script async src="https://www.googletagmanager.com/gtag/js?id=G-NXNBNVBTJS"></script>
<script>
window.dataLayer = window.dataLayer || [];
function gtag(){dataLayer.push(arguments);}
gtag('js', new Date());
gtag('config', 'G-NXNBNVBTJS');
</script>
<meta charset="UTF-8">
<title>std::list::コンストラクタ - cpprefjp C++日本語リファレンス</title>
<meta name="viewport" content="width=device-width,initial-scale=1">
<meta name="keywords" content="
C++,標準ライブラリ,リファレンス,ドキュメント,STL,std,list,std,list,function
">
<meta name="title" content="std::list::コンストラクタ - cpprefjp C++日本語リファレンス" />
<meta itemprop="name" content="std::list::コンストラクタ - cpprefjp C++日本語リファレンス" />
<meta property="og:title" content="std::list::コンストラクタ - cpprefjp C++日本語リファレンス" />
<meta property="og:url" content="https://cpprefjp.github.io/reference/list/list/op_constructor.html" />
<meta property="og:site_name" content="cpprefjp - C++日本語リファレンス" />
<meta property="og:type" content="article" />
<meta property="og:description" content="list オブジェクトの構築" />
<meta name="twitter:card" content="summary" />
<meta name="twitter:title" content="std::list::コンストラクタ - cpprefjp C++日本語リファレンス" />
<meta name="twitter:url" content="https://cpprefjp.github.io/reference/list/list/op_constructor.html" />
<meta name="twitter:description" content="list オブジェクトの構築" />
<link rel="alternate" type="application/atom+xml" title="Atom" href="https://cpprefjp.github.io/rss.xml" />
<link rel="apple-touch-icon" sizes="180x180" href="../../../static/favicons/apple-touch-icon.png?cachebust=557cd0469f26f0f797224f46d1b6e764266f07cc">
<link rel="icon" type="image/png" sizes="32x32" href="../../../static/favicons/favicon-32x32.png?cachebust=557cd0469f26f0f797224f46d1b6e764266f07cc">
<link rel="icon" type="image/png" sizes="16x16" href="../../../static/favicons/favicon-16x16.png?cachebust=557cd0469f26f0f797224f46d1b6e764266f07cc">
<link rel="manifest" href="../../../manifest.json?cachebust=557cd0469f26f0f797224f46d1b6e764266f07cc">
<meta name="theme-color" content="#f5f8fc">
<link rel="stylesheet" href="../../../static/pygments/default.css?cachebust=557cd0469f26f0f797224f46d1b6e764266f07cc">
<!-- <link rel="stylesheet" href="../../../static/css/root.css"> -->
<link href="../../../static/kunai/css/kunai-stage-0.css?cachebust=557cd0469f26f0f797224f46d1b6e764266f07cc" rel="stylesheet">
<link href="../../../static/kunai/css/kunai-stage-1.css?cachebust=557cd0469f26f0f797224f46d1b6e764266f07cc" rel="stylesheet">
<link href="../../../static/kunai/css/kunai-stage-2.css?cachebust=557cd0469f26f0f797224f46d1b6e764266f07cc" rel="stylesheet">
<link href="../../../static/kunai/css/kunai-stage-3.css?cachebust=557cd0469f26f0f797224f46d1b6e764266f07cc" rel="stylesheet">
<script type="text/javascript" src="../../../static/kunai/js/kunai-vendor.js?cachebust=557cd0469f26f0f797224f46d1b6e764266f07cc"></script>
<script type="text/javascript" src="../../../static/kunai/js/kunai.js?cachebust=557cd0469f26f0f797224f46d1b6e764266f07cc"></script>
<script type="text/javascript">
document.addEventListener('DOMContentLoaded', function() {
var kn = new Kunai;
kn.cpprefjp();
});
</script>
</head>
<body>
<header data-kunai-mdinfo="{"meta": {"header": ["list"], "namespace": ["std"], "class": ["list"], "id-type": ["function"]}, "sources": [{"id": "762cac1f22c0c5e14ab2a71c1f1528898d2d4f65", "source": "#include <list>\n#include <vector>\n#include <scoped_allocator>\n\nint main()\n{\n using li = std::list<int>;\n std::vector<li, std::scoped_allocator_adaptor<std::allocator<li>>> v;\n v.emplace_back(10u);\n}\n"}, {"id": "afbe01db16f86e86e26d86ebf5a72880d58e1ddd", "source": "#include <iostream>\n#include <list>\n#include <string>\n#include <utility>\n\ntemplate <class T>\nvoid print(const std::string& name, const std::list<T>& ls)\n{\n std::cout << name << \" : \";\n for (const T& x : ls) {\n std::cout << x << \" \";\n }\n std::cout << std::endl;\n}\n\nint main ()\n{\n // \u30c7\u30d5\u30a9\u30eb\u30c8\u69cb\u7bc9\n std::list<int> ls1;\n ::print(\"ls1\", ls1);\n\n // n \u500b\u306e\u8981\u7d20\u3092\u6301\u3064\u30ea\u30b9\u30c8\u3092\u4f5c\u6210\n std::list<int> ls2(3);\n ::print(\"ls2\", ls2);\n\n // n \u500b\u306e\u6307\u5b9a\u3055\u308c\u305f\u5024\u3092\u8981\u7d20\u306b\u6301\u3064\u30ea\u30b9\u30c8\u3092\u4f5c\u6210\n std::list<int> ls3(3, 1);\n ::print(\"ls3\", ls3);\n\n // \u7bc4\u56f2\u304b\u3089\u69cb\u7bc9\n std::list<int> ls4(ls3.begin(), ls3.end());\n ::print(\"ls4\", ls4);\n\n // \u30b3\u30d4\u30fc\u69cb\u7bc9\n std::list<int> ls5 = ls4;\n ::print(\"ls5\", ls5);\n\n // \u30e0\u30fc\u30d6\u69cb\u7bc9\n std::list<int> ls6 = std::move(ls5);\n ::print(\"ls6\", ls6);\n\n // \u521d\u671f\u5316\u5b50\u30ea\u30b9\u30c8\u3067\u69cb\u7bc9\n std::list<int> ls7 = { 1, 2, 3 };\n ::print(\"ls7\", ls7);\n}\n"}], "page_id": ["reference", "list", "list", "op_constructor"]}">
<nav class="navbar navbar-default" role="navigation">
<div class="container-fluid">
<div class="navbar-header">
<button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#navbar-collapse">
<span class="sr-only">Toggle navigation</span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
<a class="navbar-brand" href="../../../index.html">
<div class="title-wrapper clearfix">
<div class="title">cpprefjp - C++日本語リファレンス</div>
</div>
</a>
</div>
<div class="collapse navbar-collapse" id="navbar-collapse">
<ul class="nav navbar-nav navbar-right">
<li>
<div class="google-search">
<script>
(function() {
var cx = '013316413321391058734:ji_u66hl7hq';
var gcse = document.createElement('script');
gcse.type = 'text/javascript';
gcse.async = true;
gcse.src = (document.location.protocol == 'https:' ? 'https:' : 'http:') +
'//www.google.com/cse/cse.js?cx=' + cx;
var s = document.getElementsByTagName('script')[0];
s.parentNode.insertBefore(gcse, s);
})();
</script>
<div class="gcse-search"></div>
</div>
</li>
<li>
<a href="https://github.com/cpprefjp/site">GitHub Project</a>
</li>
</ul>
</div>
</div>
</nav>
</header>
<main id="main" role="main">
<div class="container-fluid">
<div class="row">
<div class="col-sm-9 col-sm-push-3" itemscope itemtype="http://schema.org/Article">
<div class="row">
<div class="col-sm-12 google-search-result">
<gcse:searchresults></gcse:searchresults>
</div>
</div>
<div class="row">
<div class="col-sm-12 content-header">
<ol class="breadcrumb">
<li itemscope itemtype="http://www.schema.org/SiteNavigationElement">
<span>
<a href="../../../index.html" itemprop="url">
<i class="fa fa-fw fa-home"></i>
</a>
</span>
</li>
<li itemscope itemtype="http://www.schema.org/SiteNavigationElement">
<span>
<a href="../../../reference.html" itemprop="url">
<span itemprop="name">リファレンス</span>
</a>
</span>
</li>
<li itemscope itemtype="http://www.schema.org/SiteNavigationElement">
<span>
<a href="../../../reference/list.html" itemprop="url">
<span itemprop="name">list</span>
</a>
</span>
</li>
<li itemscope itemtype="http://www.schema.org/SiteNavigationElement">
<span>
<a href="../../../reference/list/list.html" itemprop="url">
<span itemprop="name">list</span>
</a>
</span>
</li>
<li class="active" itemscope itemtype="http://www.schema.org/SiteNavigationElement">
<span>
<span itemprop="name">コンストラクタ</span>
</span>
</li>
</ol>
<div class="crsearch"></div>
</div>
</div>
<div class="row">
<div class="col-sm-12 edit-button">
<p class="text-right"><small>
最終更新日時:
<time itemprop="datePublished" class="js-local-time"
datetime="2026-03-21T23:12:53+09:00">
2026年03月21日 23時12分53秒 (JST)
</time>
<br/>
<span itemprop="author" itemscope itemtype="http://schema.org/Person">
<span itemprop="name">Raclamusi</span>
</span>
が更新
</small></p>
<script>
(function () {
// 最終更新日時を閲覧者のローカルタイムゾーンで表示し直す (issue #53 の正規化)。
// JS が無効な環境ではサーバ生成の JST 表記がそのまま残る。
function pad(n) { return (n < 10 ? '0' : '') + n; }
var els = document.querySelectorAll('time.js-local-time[datetime]');
for (var i = 0; i < els.length; i++) {
var el = els[i];
var d = new Date(el.getAttribute('datetime'));
if (isNaN(d.getTime())) { continue; }
var tz = '';
try {
var parts = new Intl.DateTimeFormat(undefined, { timeZoneName: 'short' }).formatToParts(d);
for (var j = 0; j < parts.length; j++) {
if (parts[j].type === 'timeZoneName') { tz = parts[j].value; break; }
}
} catch (e) {}
el.textContent = d.getFullYear() + '年' + pad(d.getMonth() + 1) + '月' + pad(d.getDate()) + '日 '
+ pad(d.getHours()) + '時' + pad(d.getMinutes()) + '分' + pad(d.getSeconds()) + '秒'
+ (tz ? ' (' + tz + ')' : '');
}
})();
</script>
<p class="text-right">
<a class="history" target="_blank" href="https://github.com/cpprefjp/site/commits/master/reference/list/list/op_constructor.md">
<span class="fa fa-fw fa-clock-o fa-flip-horizontal"></span>履歴
</a>
<a class="edit" target="_blank" href="https://github.com/cpprefjp/site/edit/master/reference/list/list/op_constructor.md">
<span class="fa fa-fw fa-pencil"></span>編集
</a>
</p>
</div>
</div>
<div class="row">
<div class="col-sm-12 content-body">
<div class="identifier-type">function</div><div class="header"><list></div><h1 itemprop="name"><span class="namespace" title="namespace std">std::</span><span class="class" title="class list">list::</span><span class="token">コンストラクタ</span></h1>
<div itemprop="articleBody"><p><div class="codehilite"><pre><span></span><code><span class="n">list</span><span class="p">();</span><span class="w"> </span><span class="c1">// (1) C++14</span>
<span class="k">constexpr</span><span class="w"> </span><span class="n">list</span><span class="p">();</span><span class="w"> </span><span class="c1">// (1) C++26</span>
<span class="n">list</span><span class="p">(</span><span class="k">const</span><span class="w"> </span><span class="n">Allocator</span><span class="o">&</span><span class="w"> </span><span class="n">a</span><span class="p">);</span><span class="w"> </span><span class="c1">// (2) C++14</span>
<span class="k">constexpr</span><span class="w"> </span><span class="n">list</span><span class="p">(</span><span class="k">const</span><span class="w"> </span><span class="n">Allocator</span><span class="o">&</span><span class="w"> </span><span class="n">a</span><span class="p">);</span><span class="w"> </span><span class="c1">// (2) C++26</span>
<span class="k">explicit</span><span class="w"> </span><span class="n">list</span><span class="p">(</span><span class="k">const</span><span class="w"> </span><span class="n">Allocator</span><span class="o">&</span><span class="w"> </span><span class="n">a</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">Allocator</span><span class="p">());</span><span class="w"> </span><span class="c1">// (1), (2) C++11 まで。C++14 で削除</span>
<span class="k">explicit</span><span class="w"> </span><span class="n">list</span><span class="p">(</span><span class="n">size_type</span><span class="w"> </span><span class="n">n</span><span class="p">,</span><span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="n">T</span><span class="o">&</span><span class="w"> </span><span class="n">value</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">T</span><span class="p">(),</span>
<span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="n">Allocator</span><span class="o">&</span><span class="w"> </span><span class="n">a</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">Allocator</span><span class="p">());</span><span class="w"> </span><span class="c1">// (3) C++03 まで。C++11 で削除</span>
<span class="n">list</span><span class="p">(</span><span class="n">size_type</span><span class="w"> </span><span class="n">n</span><span class="p">,</span><span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="n">T</span><span class="o">&</span><span class="w"> </span><span class="n">value</span><span class="p">,</span>
<span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="n">Allocator</span><span class="o">&</span><span class="w"> </span><span class="n">a</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">Allocator</span><span class="p">());</span><span class="w"> </span><span class="c1">// (3) C++11 から</span>
<span class="k">constexpr</span>
<span class="w"> </span><span class="n">list</span><span class="p">(</span><span class="n">size_type</span><span class="w"> </span><span class="n">n</span><span class="p">,</span><span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="n">T</span><span class="o">&</span><span class="w"> </span><span class="n">value</span><span class="p">,</span>
<span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="n">Allocator</span><span class="o">&</span><span class="w"> </span><span class="n">a</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">Allocator</span><span class="p">());</span><span class="w"> </span><span class="c1">// (3) C++26</span>
<span class="k">explicit</span>
<span class="w"> </span><span class="n">list</span><span class="p">(</span><span class="n">size_type</span><span class="w"> </span><span class="n">n</span><span class="p">);</span><span class="w"> </span><span class="c1">// (4) C++11。C++14 で削除</span>
<span class="k">explicit</span>
<span class="w"> </span><span class="n">list</span><span class="p">(</span><span class="n">size_type</span><span class="w"> </span><span class="n">n</span><span class="p">,</span>
<span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="n">Allocator</span><span class="o">&</span><span class="w"> </span><span class="n">a</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">Allocator</span><span class="p">());</span><span class="w"> </span><span class="c1">// (4) C++14 から</span>
<span class="k">constexpr</span><span class="w"> </span><span class="k">explicit</span>
<span class="w"> </span><span class="n">list</span><span class="p">(</span><span class="n">size_type</span><span class="w"> </span><span class="n">n</span><span class="p">,</span>
<span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="n">Allocator</span><span class="o">&</span><span class="w"> </span><span class="n">a</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">Allocator</span><span class="p">());</span><span class="w"> </span><span class="c1">// (4) C++26</span>
<span class="k">template</span><span class="w"> </span><span class="o"><</span><span class="k">class</span><span class="w"> </span><span class="nc">InputIterator</span><span class="o">></span>
<span class="n">list</span><span class="p">(</span><span class="n">InputIterator</span><span class="w"> </span><span class="n">first</span><span class="p">,</span>
<span class="w"> </span><span class="n">InputIterator</span><span class="w"> </span><span class="n">last</span><span class="p">,</span>
<span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="n">Allocator</span><span class="o">&</span><span class="w"> </span><span class="n">a</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">Allocator</span><span class="p">());</span><span class="w"> </span><span class="c1">// (5) C++03</span>
<span class="k">template</span><span class="w"> </span><span class="o"><</span><span class="k">class</span><span class="w"> </span><span class="nc">InputIterator</span><span class="o">></span>
<span class="k">constexpr</span>
<span class="w"> </span><span class="n">list</span><span class="p">(</span><span class="n">InputIterator</span><span class="w"> </span><span class="n">first</span><span class="p">,</span>
<span class="w"> </span><span class="n">InputIterator</span><span class="w"> </span><span class="n">last</span><span class="p">,</span>
<span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="n">Allocator</span><span class="o">&</span><span class="w"> </span><span class="n">a</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">Allocator</span><span class="p">());</span><span class="w"> </span><span class="c1">// (5) C++26</span>
<span class="n">list</span><span class="p">(</span><span class="k">const</span><span class="w"> </span><span class="n">list</span><span class="o">&</span><span class="w"> </span><span class="n">x</span><span class="p">);</span><span class="w"> </span><span class="c1">// (6) C++03</span>
<span class="k">constexpr</span><span class="w"> </span><span class="n">list</span><span class="p">(</span><span class="k">const</span><span class="w"> </span><span class="n">list</span><span class="o">&</span><span class="w"> </span><span class="n">x</span><span class="p">);</span><span class="w"> </span><span class="c1">// (6) C++26</span>
<span class="n">list</span><span class="p">(</span><span class="n">list</span><span class="o">&&</span><span class="w"> </span><span class="n">x</span><span class="p">);</span><span class="w"> </span><span class="c1">// (7) C++11</span>
<span class="k">constexpr</span><span class="w"> </span><span class="n">list</span><span class="p">(</span><span class="n">list</span><span class="o">&&</span><span class="w"> </span><span class="n">x</span><span class="p">);</span><span class="w"> </span><span class="c1">// (7) C++26</span>
<span class="n">list</span><span class="p">(</span><span class="k">const</span><span class="w"> </span><span class="n">list</span><span class="o">&</span><span class="w"> </span><span class="n">x</span><span class="p">,</span>
<span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="n">Allocator</span><span class="o">&</span><span class="w"> </span><span class="n">a</span><span class="p">);</span><span class="w"> </span><span class="c1">// (8) C++11</span>
<span class="n">list</span><span class="p">(</span><span class="k">const</span><span class="w"> </span><span class="n">list</span><span class="o">&</span><span class="w"> </span><span class="n">x</span><span class="p">,</span>
<span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="n"><a href="../../type_traits/type_identity.html">type_identity_t</a></span><span class="o"><</span><span class="n">Allocator</span><span class="o">>&</span><span class="w"> </span><span class="n">a</span><span class="p">);</span><span class="w"> </span><span class="c1">// (8) C++23</span>
<span class="k">constexpr</span>
<span class="w"> </span><span class="n">list</span><span class="p">(</span><span class="k">const</span><span class="w"> </span><span class="n">list</span><span class="o">&</span><span class="w"> </span><span class="n">x</span><span class="p">,</span>
<span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="n"><a href="../../type_traits/type_identity.html">type_identity_t</a></span><span class="o"><</span><span class="n">Allocator</span><span class="o">>&</span><span class="w"> </span><span class="n">a</span><span class="p">);</span><span class="w"> </span><span class="c1">// (8) C++26</span>
<span class="n">list</span><span class="p">(</span><span class="n">list</span><span class="o">&&</span><span class="w"> </span><span class="n">x</span><span class="p">,</span>
<span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="n">Allocator</span><span class="o">&</span><span class="w"> </span><span class="n">a</span><span class="p">);</span><span class="w"> </span><span class="c1">// (9) C++11</span>
<span class="n">list</span><span class="p">(</span><span class="n">list</span><span class="o">&&</span><span class="w"> </span><span class="n">x</span><span class="p">,</span>
<span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="n"><a href="../../type_traits/type_identity.html">type_identity_t</a></span><span class="o"><</span><span class="n">Allocator</span><span class="o">>&</span><span class="w"> </span><span class="n">a</span><span class="p">);</span><span class="w"> </span><span class="c1">// (9) C++23</span>
<span class="k">constexpr</span>
<span class="w"> </span><span class="n">list</span><span class="p">(</span><span class="n">list</span><span class="o">&&</span><span class="w"> </span><span class="n">x</span><span class="p">,</span>
<span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="n"><a href="../../type_traits/type_identity.html">type_identity_t</a></span><span class="o"><</span><span class="n">Allocator</span><span class="o">>&</span><span class="w"> </span><span class="n">a</span><span class="p">);</span><span class="w"> </span><span class="c1">// (9) C++26</span>
<span class="n">list</span><span class="p">(</span><span class="n"><a href="../../initializer_list/initializer_list.html">initializer_list</a></span><span class="o"><</span><span class="n">T</span><span class="o">></span><span class="w"> </span><span class="n">il</span><span class="p">,</span>
<span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="n">Allocator</span><span class="o">&</span><span class="w"> </span><span class="n">a</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">Allocator</span><span class="p">());</span><span class="w"> </span><span class="c1">// (10) C++11</span>
<span class="k">constexpr</span>
<span class="w"> </span><span class="n">list</span><span class="p">(</span><span class="n"><a href="../../initializer_list/initializer_list.html">initializer_list</a></span><span class="o"><</span><span class="n">T</span><span class="o">></span><span class="w"> </span><span class="n">il</span><span class="p">,</span>
<span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="n">Allocator</span><span class="o">&</span><span class="w"> </span><span class="n">a</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">Allocator</span><span class="p">());</span><span class="w"> </span><span class="c1">// (10) C++26</span>
<span class="k">template</span><span class="w"> </span><span class="o"><</span><span class="n">container</span><span class="o">-</span><span class="n">compatible</span><span class="o">-</span><span class="n"><a href="../../ranges/range.html">range</a></span><span class="o"><</span><span class="n">T</span><span class="o">></span><span class="w"> </span><span class="n">R</span><span class="o">></span>
<span class="n">list</span><span class="p">(</span><span class="n"><a href="../../ranges/from_range_t.html">from_range_t</a></span><span class="p">,</span><span class="w"> </span><span class="n">R</span><span class="o">&&</span><span class="w"> </span><span class="n">rg</span><span class="p">,</span>
<span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="n">Allocator</span><span class="o">&</span><span class="w"> </span><span class="n">a</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">Allocator</span><span class="p">());</span><span class="w"> </span><span class="c1">// (11) C++23</span>
<span class="k">template</span><span class="w"> </span><span class="o"><</span><span class="n">container</span><span class="o">-</span><span class="n">compatible</span><span class="o">-</span><span class="n"><a href="../../ranges/range.html">range</a></span><span class="o"><</span><span class="n">T</span><span class="o">></span><span class="w"> </span><span class="n">R</span><span class="o">></span>
<span class="k">constexpr</span>
<span class="w"> </span><span class="n">list</span><span class="p">(</span><span class="n"><a href="../../ranges/from_range_t.html">from_range_t</a></span><span class="p">,</span><span class="w"> </span><span class="n">R</span><span class="o">&&</span><span class="w"> </span><span class="n">rg</span><span class="p">,</span>
<span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="n">Allocator</span><span class="o">&</span><span class="w"> </span><span class="n">a</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">Allocator</span><span class="p">());</span><span class="w"> </span><span class="c1">// (11) C++26</span>
</code></pre></div>
</p>
<h2>概要</h2>
<p>list オブジェクトの構築</p>
<h2>効果</h2>
<ul>
<li>(1) : デフォルトコンストラクタ。アロケータを<a class="cpprefjp-defined-word" data-desc="デフォルト初期化。`T x;`構文での初期化。トリビアルにデフォルト構築可能な型の場合は初期化されず（オブジェクトのlifetimeは開始される）、そうではないクラス型はデフォルトコンストラクタで初期化する。配列型の場合は各要素が再帰的にデフォルト初期化される">デフォルト構築</a>して、空のコンテナを作る。</li>
<li>(2) : アロケータを指定して空のコンテナを作る。</li>
<li>(3) : <code>value</code> のコピーを <code>n</code> 個要素として保持した <code>list</code> を構築する。</li>
<li>(4) : <code>n</code> 個の <code>T()</code> 初期化された要素を保持した <code>list</code> を構築する。</li>
<li>(5) : <a class="cpprefjp-defined-word" data-desc="2つのイテレータで表現される半開区間を表す。C++20からイテレータと番兵で異なる型であっても指定可能になる">イテレータ範囲</a><code>[first, last)</code>を要素としてコピーした <code>list</code> を構築する。</li>
<li>(6) : コピーコンストラクタ。<code>x</code> と同じ要素を保持した <code>list</code> を構築する。</li>
<li>(7) : ムーブコンストラクタ。<code>x</code> の指す先を自分の領域として <code>list</code> を構築する。</li>
<li>(8) : アロケータを指定したコピーコンストラクタ。</li>
<li>(9) : アロケータを指定したムーブコンストラクタ。</li>
<li>(10) : 初期化子リストを受け取るコンストラクタ。<code>list(il.<a href="../../initializer_list/initializer_list/begin.html">begin</a>(), il.<a href="../../initializer_list/initializer_list/end.html">end</a>(), a)</code> と等価。</li>
<li>(11) : Rangeコンストラクタ。Range <code>rg</code> の要素で <code>list</code> を構築する。</li>
</ul>
<h2><a class="cpprefjp-defined-word" data-desc="関数等の意味論を構成する要素の1つ。Complexity。関数が使うアルゴリズムの空間計算量・時間計算量">計算量</a></h2>
<ul>
<li>(1), (2) : 定数時間</li>
<li>(3), (4) : <code>n</code> に対して線形時間</li>
<li>(5) : <code><a href="../../iterator/distance.html">distance</a>(first, last)</code> に対して線形時間</li>
<li>(6), (8) : <code>x.<a href="size.html">size</a>()</code> に対して線形時間</li>
<li>(7) : 定数時間</li>
<li>(9) : <code>a == x.<a href="get_allocator.html">get_allocator</a>()</code> であれば定数時間。そうでなければ <code>x.<a href="size.html">size</a>()</code> に対して線形時間</li>
<li>(10) : <code>il.<a href="../../initializer_list/initializer_list/size.html">size</a>()</code> に対して線形時間</li>
<li>(11) : <code><a href="../../iterator/ranges_distance.html">ranges::distance</a>(rg)</code> に対して線形時間</li>
</ul>
<h2>備考</h2>
<ul>
<li>(5) の形式は、C++03 までは <code>InputIterator</code> が整数型の場合には <code>list(static_cast<typename list::size_type>(first), static_cast<typename list::value_type>(last), a)</code> と等価とされていたが、C++11 では <code>InputIterator</code> が入力イテレータの要件を満たさなければ<a class="cpprefjp-defined-word" data-desc="関数呼び出し時に、同名の関数の中から実際に呼び出す関数を決定する処理。このときの候補になることを、オーバーロード解決に参加するという">オーバーロード解決</a>に参加しないように変更された。</li>
<li>
<p>C++11 では、(3) の形式の引数 <code>value</code> に関するデフォルト引数が削除され、新たに (4) の形式が追加された。<br />
これは、デフォルト引数を使用すると、引数 <code>value</code> の<a class="cpprefjp-defined-word" data-desc="`T x;`構文での初期化。トリビアルにデフォルト構築可能な型の場合は初期化されず（オブジェクトのlifetimeは開始される）、そうではないクラス型はデフォルトコンストラクタで初期化する。配列型の場合は各要素が再帰的にデフォルト初期化される">デフォルト初期化</a> 1 回＋<code>list</code> の要素へのコピー初期化 <code>n</code> 回のコンストラクタ呼び出しが必要となるが、デフォルト引数でなければ <code>list</code> の要素への<a class="cpprefjp-defined-word" data-desc="`T x;`構文での初期化。トリビアルにデフォルト構築可能な型の場合は初期化されず（オブジェクトのlifetimeは開始される）、そうではないクラス型はデフォルトコンストラクタで初期化する。配列型の場合は各要素が再帰的にデフォルト初期化される">デフォルト初期化</a> <code>n</code> 回のコンストラクタ呼び出しで済むためである。</p>
</li>
<li>
<p>C++14 では、(1) の形式と (2) の形式がデフォルト引数を使用しない 2 つの<a class="cpprefjp-defined-word" data-desc="同名の関数を異なる引数・テンプレート・制約などで複数定義すること。または同名の関数の集合">オーバーロード</a>に分割された。<br />
これは、デフォルトコンストラクタに <code>explicit</code> が付いていると、</p>
<p><div class="codehilite"><pre><span></span><code><span class="n"><a href="../list.html">std::list</a></span><span class="o"><</span><span class="kt">int</span><span class="o">></span><span class="w"> </span><span class="n">l</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="p">{};</span>
</code></pre></div>
</p>
<p>のようなコード（C++11 から導入された、コピーリスト初期化によるデフォルトコンストラクタ呼び出し）がエラーになってしまうためである。</p>
</li>
<li>
<p>C++14 では、(4) の形式に引数が追加された。<br />
これは、変更されないと <code>n</code> のみを引数にとるアロケータ使用構築（uses-allocator construction）に失敗してしまうためである。
具体的には、C++11 では以下のようなコードがエラーになってしまう。</p>
<p><div class="yata" id="762cac1f22c0c5e14ab2a71c1f1528898d2d4f65"><div class="codehilite"><pre><span></span><code><span class="cp">#include <a href="../../list.html"><list></a></span>
<span class="cp">#include <a href="../../vector.html"><vector></a></span>
<span class="cp">#include <a href="../../scoped_allocator.html"><scoped_allocator></a></span>
<span class="kt">int</span><span class="w"> </span><span class="nf">main</span><span class="p">()</span>
<span class="p">{</span>
<span class="w"> </span><span class="k">using</span><span class="w"> </span><span class="n">li</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n"><a href="../list.html">std::list</a></span><span class="o"><</span><span class="kt">int</span><span class="o">></span><span class="p">;</span>
<span class="w"> </span><span class="n"><a href="../../vector/vector.html">std::vector</a></span><span class="o"><</span><span class="n">li</span><span class="p">,</span><span class="w"> </span><span class="n"><a href="../../scoped_allocator/scoped_allocator_adaptor.html">std::scoped_allocator_adaptor</a></span><span class="o"><</span><span class="n"><a href="../../memory/allocator.html">std::allocator</a></span><span class="o"><</span><span class="n">li</span><span class="o">>>></span><span class="w"> </span><span class="n">v</span><span class="p">;</span>
<span class="w"> </span><span class="n"><a href="../../vector/vector/emplace_back.html">v.emplace_back</a></span><span class="p">(</span><span class="mi">10u</span><span class="p">);</span>
<span class="p">}</span>
</code></pre></div>
</div></p>
</li>
<li>
<p>C++23 では、(8) と (9) のアロケータパラメータの型が <code>const Allocator&</code> から <code>const type_identity_t<Allocator>&</code> に変更された。
これは、クラステンプレートのテンプレート引数推論 (CTAD) の際に、コピー/ムーブ元の <code>list</code> から推論される <code>Allocator</code> と、アロケータ引数から推論される型が異なる場合に推論が失敗する問題を修正するためである。<code><a href="../../type_traits/type_identity.html">type_identity_t</a></code> で包むことで、アロケータ引数が非推論コンテキストとなり、アロケータの型はコピー/ムーブ元のみから推論されるようになる。</p>
</li>
</ul>
<h2>例</h2>
<p><div class="yata" id="afbe01db16f86e86e26d86ebf5a72880d58e1ddd"><div class="codehilite"><pre><span></span><code><span class="cp">#include <a href="../../iostream.html"><iostream></a></span>
<span class="cp">#include <a href="../../list.html"><list></a></span>
<span class="cp">#include <a href="../../string.html"><string></a></span>
<span class="cp">#include <a href="../../utility.html"><utility></a></span>
<span class="k">template</span><span class="w"> </span><span class="o"><</span><span class="k">class</span><span class="w"> </span><span class="nc">T</span><span class="o">></span>
<span class="kt">void</span><span class="w"> </span><span class="n">print</span><span class="p">(</span><span class="k">const</span><span class="w"> </span><span class="n"><a href="../../string/basic_string.html">std::string</a></span><span class="o">&</span><span class="w"> </span><span class="n">name</span><span class="p">,</span><span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="n"><a href="../list.html">std::list</a></span><span class="o"><</span><span class="n">T</span><span class="o">>&</span><span class="w"> </span><span class="n">ls</span><span class="p">)</span>
<span class="p">{</span>
<span class="w"> </span><span class="n"><a href="../../iostream/cout.html">std::cout</a></span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n">name</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="s">" : "</span><span class="p">;</span>
<span class="w"> </span><span class="k">for</span><span class="w"> </span><span class="p">(</span><span class="k">const</span><span class="w"> </span><span class="n">T</span><span class="o">&</span><span class="w"> </span><span class="n">x</span><span class="w"> </span><span class="o">:</span><span class="w"> </span><span class="n">ls</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
<span class="w"> </span><span class="n"><a href="../../iostream/cout.html">std::cout</a></span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n">x</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="s">" "</span><span class="p">;</span>
<span class="w"> </span><span class="p">}</span>
<span class="w"> </span><span class="n"><a href="../../iostream/cout.html">std::cout</a></span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n"><a href="../../ostream/endl.html">std::endl</a></span><span class="p">;</span>
<span class="p">}</span>
<span class="kt">int</span><span class="w"> </span><span class="n">main</span><span class="w"> </span><span class="p">()</span>
<span class="p">{</span>
<span class="w"> </span><span class="c1">// デフォルト構築</span>
<span class="w"> </span><span class="n"><a href="../list.html">std::list</a></span><span class="o"><</span><span class="kt">int</span><span class="o">></span><span class="w"> </span><span class="n">ls1</span><span class="p">;</span>
<span class="w"> </span><span class="o">::</span><span class="n">print</span><span class="p">(</span><span class="s">"ls1"</span><span class="p">,</span><span class="w"> </span><span class="n">ls1</span><span class="p">);</span>
<span class="w"> </span><span class="c1">// n 個の要素を持つリストを作成</span>
<span class="w"> </span><span class="n"><a href="../list.html">std::list</a></span><span class="o"><</span><span class="kt">int</span><span class="o">></span><span class="w"> </span><span class="n">ls2</span><span class="p">(</span><span class="mi">3</span><span class="p">);</span>
<span class="w"> </span><span class="o">::</span><span class="n">print</span><span class="p">(</span><span class="s">"ls2"</span><span class="p">,</span><span class="w"> </span><span class="n">ls2</span><span class="p">);</span>
<span class="w"> </span><span class="c1">// n 個の指定された値を要素に持つリストを作成</span>
<span class="w"> </span><span class="n"><a href="../list.html">std::list</a></span><span class="o"><</span><span class="kt">int</span><span class="o">></span><span class="w"> </span><span class="n">ls3</span><span class="p">(</span><span class="mi">3</span><span class="p">,</span><span class="w"> </span><span class="mi">1</span><span class="p">);</span>
<span class="w"> </span><span class="o">::</span><span class="n">print</span><span class="p">(</span><span class="s">"ls3"</span><span class="p">,</span><span class="w"> </span><span class="n">ls3</span><span class="p">);</span>
<span class="w"> </span><span class="c1">// 範囲から構築</span>
<span class="w"> </span><span class="n"><a href="../list.html">std::list</a></span><span class="o"><</span><span class="kt">int</span><span class="o">></span><span class="w"> </span><span class="n">ls4</span><span class="p">(</span><span class="n"><a href="begin.html">ls3.begin()</a></span><span class="p">,</span><span class="w"> </span><span class="n"><a href="end.html">ls3.end()</a></span><span class="p">);</span>
<span class="w"> </span><span class="o">::</span><span class="n">print</span><span class="p">(</span><span class="s">"ls4"</span><span class="p">,</span><span class="w"> </span><span class="n">ls4</span><span class="p">);</span>
<span class="w"> </span><span class="c1">// コピー構築</span>
<span class="w"> </span><span class="n"><a href="../list.html">std::list</a></span><span class="o"><</span><span class="kt">int</span><span class="o">></span><span class="w"> </span><span class="n">ls5</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">ls4</span><span class="p">;</span>
<span class="w"> </span><span class="o">::</span><span class="n">print</span><span class="p">(</span><span class="s">"ls5"</span><span class="p">,</span><span class="w"> </span><span class="n">ls5</span><span class="p">);</span>
<span class="w"> </span><span class="c1">// ムーブ構築</span>
<span class="w"> </span><span class="n"><a href="../list.html">std::list</a></span><span class="o"><</span><span class="kt">int</span><span class="o">></span><span class="w"> </span><span class="n">ls6</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n"><a href="../../utility/move.html">std::move</a></span><span class="p">(</span><span class="n">ls5</span><span class="p">);</span>
<span class="w"> </span><span class="o">::</span><span class="n">print</span><span class="p">(</span><span class="s">"ls6"</span><span class="p">,</span><span class="w"> </span><span class="n">ls6</span><span class="p">);</span>
<span class="w"> </span><span class="c1">// 初期化子リストで構築</span>
<span class="w"> </span><span class="n"><a href="../list.html">std::list</a></span><span class="o"><</span><span class="kt">int</span><span class="o">></span><span class="w"> </span><span class="n">ls7</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="p">{</span><span class="w"> </span><span class="mi">1</span><span class="p">,</span><span class="w"> </span><span class="mi">2</span><span class="p">,</span><span class="w"> </span><span class="mi">3</span><span class="w"> </span><span class="p">};</span>
<span class="w"> </span><span class="o">::</span><span class="n">print</span><span class="p">(</span><span class="s">"ls7"</span><span class="p">,</span><span class="w"> </span><span class="n">ls7</span><span class="p">);</span>
<span class="p">}</span>
</code></pre></div>
</div></p>
<h3>出力</h3>
<p><pre><code>ls1 :
ls2 : 0 0 0
ls3 : 1 1 1
ls4 : 1 1 1
ls5 : 1 1 1
ls6 : 1 1 1
ls7 : 1 2 3
</code></pre></p>
<h2>参照</h2>
<ul>
<li><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2679.pdf" target="_blank">N2679 Initializer Lists for Standard Containers(Revision 1)</a><ul>
<li>(10)の経緯となる提案文書</li>
</ul>
</li>
<li><a href="http://cplusplus.github.io/LWG/lwg-defects.html#2193" target="_blank">LWG 2193. Default constructors for standard library containers are explicit</a><br />
<code>explicit list(const Allocator& a = Allocator())</code> を 2 つの<a class="cpprefjp-defined-word" data-desc="同名の関数を異なる引数・テンプレート・制約などで複数定義すること。または同名の関数の集合">オーバーロード</a>に分割するきっかけとなったレポート</li>
<li><a href="http://cplusplus.github.io/LWG/lwg-defects.html#2210" target="_blank">LWG 2210. Missing allocator-extended constructor for allocator-aware containers</a><br />
<code>explicit list(size_type n)</code> にアロケータ引数を追加するきっかけとなったレポート<br />
なお、Discussion の例はアロケータの型が誤っているので注意</li>
<li><a href="https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2021/p1518r2.html" target="_blank">P1518R2 Stop Overconstraining Allocators in Container Deduction Guides</a><ul>
<li>C++23でのアロケータ引数を<code>type_identity_t</code>で包む変更</li>
</ul>
</li>
<li><a href="https://open-std.org/jtc1/sc22/wg21/docs/papers/2025/p3372r3.html" target="_blank">P3372R3 constexpr containers and adaptors</a></li>
</ul></div>
</div>
</div>
</div>
<div id="sidebar" class="col-sm-3 col-sm-pull-9">
</div>
</div>
</div>
</main>
<footer class="footer navbar navbar-default">
<div class="container-fluid">
<p><small>
本サイトの情報は、
<a href="https://creativecommons.org/licenses/by/4.0/deed.ja" rel="nofollow">クリエイティブ・コモンズ 表示 4.0 非移植 ライセンス(CC BY)</a>
の下に提供されています。
</small></p>
</div>
</footer>
</body>
</html>