klarkxy/hustoj
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
Files
90010113ddacfb181cc4cfa007fb53634e2bc12c
hustoj/web/cppreference-zh/chmhelp/cpp-iterator-counted_iterator-operator_2a.html
klarkxy 196e706fe4 上传cppreference
2025-08-01 12:57:54 +08:00

104 lines
8.4 KiB
HTML
Raw Blame History

<!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::counted_iterator&lt;I&gt;::operator*,-&gt;</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_iterator_counted_iterator_operator 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::counted_iterator&lt;I&gt;::</span>operator*,-&gt;</h1>
<div id="bodyContent">
<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-iterator.html">iterator</a>&lrm; | <a href="cpp-iterator-counted_iterator.html">counted iterator</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-dcl t-since-cxx20">
<td>
<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> decltype<span class="br0">(</span><span class="kw4">auto</span><span class="br0">)</span> operator<span class="sy2">*</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span></span></div>
</td>
<td>(1)</td>
<td><span class="t-mark-rev t-since-cxx20">(C++20 &#36215;)</span></td>
</tr>
<tr class="t-dcl t-since-cxx20">
<td>
<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> decltype<span class="br0">(</span><span class="kw4">auto</span><span class="br0">)</span> operator<span class="sy2">*</span><span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span><br />
&nbsp; &nbsp; requires <span class="coMULTI">/*dereferenceable*/</span><span class="sy1">&lt;</span><span class="kw4">const</span> I<span class="sy1">&gt;</span><span class="sy4">;</span></span></div>
</td>
<td>(2)</td>
<td><span class="t-mark-rev t-since-cxx20">(C++20 &#36215;)</span></td>
</tr>
<tr class="t-dcl t-since-cxx20">
<td>
<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> <span class="kw4">auto</span> operator<span class="sy2">-</span><span class="sy1">&gt;</span><span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><br />
&nbsp; &nbsp; requires std<span class="sy4">::</span><span class="me2">contiguous_iterator</span><span class="sy1">&lt;</span>I<span class="sy1">&gt;</span><span class="sy4">;</span></span></div>
</td>
<td>(3)</td>
<td><span class="t-mark-rev t-since-cxx20">(C++20 &#36215;)</span></td>
</tr>
<tr class="t-dcl-sep">
<td></td>
<td></td>
<td></td>
</tr>
</tbody>
</table>
<div class="t-li1"><span class="t-li">1-2)</span> &#36820;&#22238;&#21040;&#24403;&#21069;&#20803;&#32032;&#30340;&#24341;&#29992;&#12290;&#33509; <span class="t-c"><span class="mw-geshi cpp source-cpp">this<span class="sy2">-</span><span class="sy1">&gt;</span>count<span class="br0">(</span><span class="br0">)</span> <span class="sy1">&lt;=</span> <span class="nu0">0</span></span></span> &#21017;&#34892;&#20026;&#26410;&#23450;&#20041;&#12290;&#20989;&#25968;&#20307;&#31561;&#20215;&#20110; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">return</span> <span class="sy2">*</span>current<span class="sy4">;</span></span></span> &#12290;</div>
<div class="t-li1"><span class="t-li">3)</span> &#36820;&#22238;&#25351;&#21521;&#24403;&#21069;&#20803;&#32032;&#30340;&#25351;&#38024;&#12290;&#20989;&#25968;&#20307;&#31561;&#20215;&#20110; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">return</span> std<span class="sy4">::</span><span class="me2">to_address</span><span class="br0">(</span>current<span class="br0">)</span><span class="sy4">;</span></span></span> &#12290;</div>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
<p>&#65288;&#26080;&#65289;</p>
<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">&#36820;&#22238;&#20540;</span></h3>
<p>&#25351;&#21521;&#24403;&#21069;&#20803;&#32032;&#30340;&#24341;&#29992;&#25110;&#25351;&#38024;&#12290;</p>
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">&#31034;&#20363;</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 &lt;complex&gt;</span>
<span class="co2">#include &lt;iostream&gt;</span>
<span class="co2">#include &lt;iterator&gt;</span>
<span class="kw1">using</span> std<span class="sy4">::</span><span class="me2">operator</span><span class="st0">&quot;&quot;</span>i<span class="sy4">;</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
<span class="kw4">const</span> <span class="kw4">auto</span> il <span class="sy1">=</span> <span class="br0">{</span> <span class="nu0">1</span>.<span class="me1">i</span>, <span class="nu0">2</span>.<span class="me1">i</span>, <span class="nu0">3</span>.<span class="me1">i</span>, <span class="nu0">4</span>.<span class="me1">i</span>, <span class="nu0">5</span>.<span class="me1">i</span> <span class="br0">}</span><span class="sy4">;</span>
<span class="kw1">for</span> <span class="br0">(</span>std<span class="sy4">::</span><span class="me2">counted_iterator</span> i<span class="br0">{</span>il.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span> <span class="sy2">+</span> <span class="nu0">1</span>, <span class="nu0">3</span><span class="br0">}</span><span class="sy4">;</span> i <span class="sy3">!</span><span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">default_sentinel</span><span class="sy4">;</span> <span class="sy2">++</span>i<span class="br0">)</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="sy2">*</span>i <span class="sy1">&lt;&lt;</span> <span class="st0">&#39; &#39;</span><span class="sy4">;</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="sy4">;</span>
<span class="kw1">for</span> <span class="br0">(</span>std<span class="sy4">::</span><span class="me2">counted_iterator</span> i<span class="br0">{</span>il.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span> <span class="sy2">+</span> <span class="nu0">1</span>, <span class="nu0">3</span><span class="br0">}</span><span class="sy4">;</span> i <span class="sy3">!</span><span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">default_sentinel</span><span class="sy4">;</span> <span class="sy2">++</span>i<span class="br0">)</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> i<span class="sy2">-</span><span class="sy1">&gt;</span>imag<span class="br0">(</span><span class="br0">)</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&#39; &#39;</span><span class="sy4">;</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="sy4">;</span>
<span class="br0">}</span></pre></div>
</div>
<p>&#36755;&#20986;&#65306;</p>
<div dir="ltr" class="mw-geshi" style="text-align: left;">
<div class="text source-text">
<pre class="de1">(0,2) (0,3) (0,4)
2 3 4</pre></div>
</div>
</div>
<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">&#21442;&#38405;</span></h3>
<table class="t-dsc-begin">
<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-iterator-counted_iterator-operator_at.html"><span class="t-lines"><span>operator[]</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
</div>
</td>
<td>&#25353;&#32034;&#24341;&#35775;&#38382;&#20803;&#32032;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
</tr>
</table>
</div>
<div class="visualClear"></div>
</div>
</div>
</div>
</body>
</html>
Reference in New Issue View Git Blame Copy Permalink