238 lines
16 KiB
HTML
238 lines
16 KiB
HTML
<!DOCTYPE html>
|
|
<html lang="zh" dir="ltr" class="client-nojs" xmlns="http://www.w3.org/1999/xhtml" xml:lang="zh">
|
|
<head><meta http-equiv="x-ua-compatible" content="ie=edge">
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
|
|
<title>std::raw_storage_iterator</title>
|
|
<link rel="stylesheet" href="ext.css" />
|
|
<link rel="stylesheet" href="site_modules.css" />
|
|
</head>
|
|
<body class="mediawiki ltr sitedir-ltr ns-0 ns-subject page-cpp_memory_raw_storage_iterator skin-cppreference2 action-view cpp-navbar">
|
|
<div id="cpp-content-base">
|
|
<div id="content"><a id="top"></a>
|
|
<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::</span>raw_storage_iterator</h1>
|
|
<div id="bodyContent">
|
|
<div id="contentSub"><span class="subpages">< <a href="cpp.html">cpp</a>‎ | <a href="cpp-memory.html">memory</a></span></div>
|
|
<div id="mw-content-text" lang="zh" dir="ltr" class="mw-content-ltr" xml:lang="zh">
|
|
<table class="t-dcl-begin">
|
|
<tbody>
|
|
<tr class="t-dsc-header">
|
|
<td>
|
|
<div>定义于头文件 <code><a href="cpp-header-memory.html"><memory></a></code></div>
|
|
</td>
|
|
<td></td>
|
|
<td></td>
|
|
</tr>
|
|
</tbody>
|
|
<tbody class="t-dcl-rev">
|
|
<tr class="t-dcl t-until-cxx17">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> OutputIt, <span class="kw1">class</span> T <span class="sy1">></span><br /></span>
|
|
<p><span class="kw1">class</span> raw_storage_iterator<br /></p>
|
|
<span class="sy4">:</span> <span class="kw1">public</span> <a href="cpp-iterator-iterator.html"><span class="kw657">std::<span class="me2">iterator</span></span></a><span class="sy1"><</span><a href="cpp-iterator-iterator_tags.html"><span class="kw653">std::<span class="me2">output_iterator_tag</span></span></a>, <span class="kw4">void</span>, <span class="kw4">void</span>, <span class="kw4">void</span>, <span class="kw4">void</span><span class="sy1">></span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-until-cxx17">(C++17 前)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx17 t-until-cxx20">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> OutputIt, <span class="kw1">class</span> T <span class="sy1">></span><br />
|
|
<span class="kw1">class</span> raw_storage_iterator<span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx17">(C++17 起)</span><br />
|
|
<span class="t-mark">(弃用)</span><br />
|
|
<span class="t-mark-rev t-until-cxx20">(C++20 中移除)</span></td>
|
|
</tr>
|
|
</tbody>
|
|
<tbody>
|
|
<tr class="t-dcl-sep">
|
|
<td></td>
|
|
<td></td>
|
|
<td></td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>输出迭代器 <code>std::raw_storage_iterator</code> 使得标准算法能存储结果于未初始化内存。凡在算法写 <code>T</code> 类型对象到解引用后的迭代器时，对象被复制构造到该迭代器所指向的未初始化存储中的位置。模板形参 <code>OutputIt</code> 是任何满足<a href="cpp-named_req-OutputIterator.html"><span style="font-style:italic">老式输出迭代器</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(LegacyOutputIterator)</span></a> 要求的类型，并拥有定义为返回对象的 <span class="t-c"><span class="mw-geshi cpp source-cpp">operator<span class="sy2">*</span></span></span> ， <span class="t-c"><span class="mw-geshi cpp source-cpp">operator<span class="sy3">&</span></span></span> 对该对象返回 <code>T*</code> 类型值。通常，以类型 <code>T*</code> 为 <code>OutputIt</code> 。</p>
|
|
<h3><span class="mw-headline" id=".E7.B1.BB.E5.9E.8B.E8.A6.81.E6.B1.82">类型要求</span></h3>
|
|
<table class="t-par-begin">
|
|
<tr class="t-par-req">
|
|
<td colspan="3">-
|
|
<div class="spacer"></div>
|
|
<code>OutputIt</code> 必须满足<a href="cpp-named_req-OutputIterator.html"><span style="font-style:italic">老式输出迭代器</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(LegacyOutputIterator)</span></a> 的要求。</td>
|
|
</tr>
|
|
</table>
|
|
<h3><span class="mw-headline" id=".E6.88.90.E5.91.98.E5.87.BD.E6.95.B0">成员函数</span></h3>
|
|
<table class="t-dsc-begin">
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div t-dsc-member-nobold-div">
|
|
<div><a href="cpp-memory-raw_storage_iterator-raw_storage_iterator.html"><span class="t-lines"><span>(构造函数)</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>创建新的 <code>raw_storage_iterator</code><br />
|
|
<span class="t-mark">(公开成员函数)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-memory-raw_storage_iterator-operator=.html"><span class="t-lines"><span>operator=</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>在缓冲区中的被指向位置构造对象<br />
|
|
<span class="t-mark">(公开成员函数)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-memory-raw_storage_iterator-operator*.html"><span class="t-lines"><span>operator*</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>解引用迭代器<br />
|
|
<span class="t-mark">(公开成员函数)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-memory-raw_storage_iterator-operator_arith.html"><span class="t-lines"><span>operator++</span><span>operator++<span class="t-dsc-small">(int)</span></span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>推进迭代器<br />
|
|
<span class="t-mark">(公开成员函数)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-memory-raw_storage_iterator-base.html"><span class="t-lines"><span>base</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx17">(C++17 起)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>提供到被包装迭代器的访问<br />
|
|
<span class="t-mark">(公开成员函数)</span></td>
|
|
</tr>
|
|
</table>
|
|
<h3><span class="mw-headline" id=".E6.88.90.E5.91.98.E7.B1.BB.E5.9E.8B">成员类型</span></h3>
|
|
<table class="t-dsc-begin">
|
|
<tr class="t-dsc-hitem">
|
|
<td>成员类型</td>
|
|
<td>定义</td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td><code>iterator_category</code></td>
|
|
<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-iterator-iterator_tags.html"><span class="kw653">std::<span class="me2">output_iterator_tag</span></span></a></span></span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td><code>value_type</code></td>
|
|
<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">void</span></span></span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td><code>difference_type</code></td>
|
|
<td>
|
|
<table class="t-rev-begin t-rev-begin-noborder">
|
|
<tr class="t-rev t-until-cxx20">
|
|
<td>
|
|
<p><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">void</span></span></span></p>
|
|
</td>
|
|
<td><span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
|
|
</tr>
|
|
<tr class="t-rev t-since-cxx20">
|
|
<td>
|
|
<p><span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-types-ptrdiff_t.html"><span class="kw101">std::<span class="me2">ptrdiff_t</span></span></a></span></span></p>
|
|
</td>
|
|
<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
|
|
</tr>
|
|
</table>
|
|
</td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td><code>pointer</code></td>
|
|
<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">void</span></span></span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td><code>reference</code></td>
|
|
<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">void</span></span></span></td>
|
|
</tr>
|
|
</table>
|
|
<table class="t-rev-begin">
|
|
<tr class="t-rev t-until-cxx17">
|
|
<td>
|
|
<p>要求通过从 <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-iterator-iterator.html"><span class="kw657">std::<span class="me2">iterator</span></span></a><span class="sy1"><</span><a href="cpp-iterator-iterator_tags.html"><span class="kw653">std::<span class="me2">output_iterator_tag</span></span></a>, <span class="kw4">void</span>, <span class="kw4">void</span>, <span class="kw4">void</span>, <span class="kw4">void</span><span class="sy1">></span></span></span> 继承获得成员类型 <code>iterator_category</code>、 <code>value_type</code>、 <code>difference_type</code>、 <code>pointer</code> 及 <code>reference</code> 。</p>
|
|
</td>
|
|
<td><span class="t-mark-rev t-until-cxx17">(C++17 前)</span></td>
|
|
</tr>
|
|
</table>
|
|
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">示例</span></h3>
|
|
<div class="t-example">
|
|
<div class="t-example-live-link"></div>
|
|
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
|
<div class="cpp source-cpp">
|
|
<pre class="de1"><span class="co2">#include <iostream></span>
|
|
<span class="co2">#include <string></span>
|
|
<span class="co2">#include <memory></span>
|
|
<span class="co2">#include <algorithm></span>
|
|
|
|
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
|
|
<span class="br0">{</span>
|
|
<span class="kw4">const</span> <a href="cpp-string-basic_string.html"><span class="kw1229">std::<span class="me2">string</span></span></a> s<span class="br0">[</span><span class="br0">]</span> <span class="sy1">=</span> <span class="br0">{</span><span class="st0">"This"</span>, <span class="st0">"is"</span>, <span class="st0">"a"</span>, <span class="st0">"test"</span>, <span class="st0">"."</span><span class="br0">}</span><span class="sy4">;</span>
|
|
<a href="cpp-string-basic_string.html"><span class="kw1229">std::<span class="me2">string</span></span></a><span class="sy2">*</span> p <span class="sy1">=</span> <a href="cpp-memory-allocator.html"><span class="kw700">std::<span class="me2">allocator</span></span></a><span class="sy1"><</span><a href="cpp-string-basic_string.html"><span class="kw1229">std::<span class="me2">string</span></span></a><span class="sy1">></span><span class="br0">(</span><span class="br0">)</span>.<span class="me1">allocate</span><span class="br0">(</span><span class="nu0">5</span><span class="br0">)</span><span class="sy4">;</span>
|
|
|
|
<a href="cpp-algorithm-copy.html"><span class="kw1581">std::<span class="me2">copy</span></span></a><span class="br0">(</span><a href="cpp-iterator-begin.html"><span class="kw676">std::<span class="me2">begin</span></span></a><span class="br0">(</span>s<span class="br0">)</span>, <a href="cpp-iterator-end.html"><span class="kw680">std::<span class="me2">end</span></span></a><span class="br0">(</span>s<span class="br0">)</span>,
|
|
std<span class="sy4">::</span><span class="me2">raw_storage_iterator</span><span class="sy1"><</span><a href="cpp-string-basic_string.html"><span class="kw1229">std::<span class="me2">string</span></span></a><span class="sy2">*</span>, <a href="cpp-string-basic_string.html"><span class="kw1229">std::<span class="me2">string</span></span></a><span class="sy1">></span><span class="br0">(</span>p<span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
|
|
|
|
<span class="kw1">for</span><span class="br0">(</span><a href="cpp-string-basic_string.html"><span class="kw1229">std::<span class="me2">string</span></span></a><span class="sy2">*</span> i <span class="sy1">=</span> p<span class="sy4">;</span> i<span class="sy3">!</span><span class="sy1">=</span>p<span class="sy2">+</span><span class="nu0">5</span><span class="sy4">;</span> <span class="sy2">++</span>i<span class="br0">)</span> <span class="br0">{</span>
|
|
<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <span class="sy2">*</span>i <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span>
|
|
i<span class="sy2">-</span><span class="sy1">></span>~basic_string<span class="sy1"><</span><span class="kw4">char</span><span class="sy1">></span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
|
|
<span class="br0">}</span>
|
|
<a href="cpp-memory-allocator.html"><span class="kw700">std::<span class="me2">allocator</span></span></a><span class="sy1"><</span><a href="cpp-string-basic_string.html"><span class="kw1229">std::<span class="me2">string</span></span></a><span class="sy1">></span><span class="br0">(</span><span class="br0">)</span>.<span class="me1">deallocate</span><span class="br0">(</span>p, <span class="nu0">5</span><span class="br0">)</span><span class="sy4">;</span>
|
|
<span class="br0">}</span></pre></div>
|
|
</div>
|
|
<p>输出：</p>
|
|
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
|
<div class="text source-text">
|
|
<pre class="de1">This
|
|
is
|
|
a
|
|
test
|
|
.</pre></div>
|
|
</div>
|
|
</div>
|
|
<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">参阅</span></h3>
|
|
<table class="t-dsc-begin">
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-memory-allocator_traits.html"><span class="t-lines"><span>allocator_traits</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>提供关于分配器类型的信息<br />
|
|
<span class="t-mark">(类模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-memory-scoped_allocator_adaptor.html"><span class="t-lines"><span>scoped_allocator_adaptor</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>为多级容器实现的多级分配器<br />
|
|
<span class="t-mark">(类模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-memory-uses_allocator.html"><span class="t-lines"><span>uses_allocator</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>检查指定的类型是否支持使用分配器的构造<br />
|
|
<span class="t-mark">(类模板)</span></td>
|
|
</tr>
|
|
</table>
|
|
</div>
|
|
<div class="visualClear"></div>
|
|
</div>
|
|
</div>
|
|
</div>
|
|
</body>
|
|
</html>
|