668 lines
53 KiB
HTML
668 lines
53 KiB
HTML
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<title>std::basic_string<CharT,Traits,Allocator>::basic_string</title>
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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::basic_string<CharT,Traits,Allocator>::</span>basic_string</h1>
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<div id="bodyContent">
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<div id="contentSub"><span class="subpages">< <a href="cpp.html">cpp</a>‎ | <a href="cpp-string.html">string</a>‎ | <a href="cpp-string-basic_string.html">basic string</a></span></div>
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<div id="mw-content-text" lang="zh" dir="ltr" class="mw-content-ltr" xml:lang="zh">
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<td rowspan="142">(1)</td>
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span><br />
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<span class="kw1">explicit</span> basic_string<span class="br0">(</span> <span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-until-cxx17">(C++17 前)</span></td>
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<tr class="t-dcl t-since-cxx17 t-until-cxx20">
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="br0">(</span><span class="br0">)</span> <span class="kw1">noexcept</span><span class="br0">(</span><span class="kw1">noexcept</span><span class="br0">(</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><span class="br0">)</span> <span class="sy4">:</span><br /></span>
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<p> basic_string<span class="br0">(</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span> <span class="br0">{</span><span class="br0">}</span><br /></p>
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<span class="kw1">explicit</span> basic_string<span class="br0">(</span> <span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></div>
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<td><span class="t-mark-rev t-since-cxx17">(C++17 起)</span><br />
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<span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> basic_string<span class="br0">(</span><span class="br0">)</span> <span class="kw1">noexcept</span><span class="br0">(</span><span class="kw1">noexcept</span><span class="br0">(</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><span class="br0">)</span> <span class="sy4">:</span><br /></span>
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<p> basic_string<span class="br0">(</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span> <span class="br0">{</span><span class="br0">}</span><br /></p>
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<span class="kw1">explicit</span> <span class="kw4">constexpr</span> basic_string<span class="br0">(</span> <span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></div>
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</td>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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<td rowspan="142">(2)</td>
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="br0">(</span> size_type count,<br /></span>
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<p> CharT ch,<br /></p>
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<span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="sy1">=</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td><span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
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<tr class="t-dcl t-since-cxx20">
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> basic_string<span class="br0">(</span> size_type count,<br /></span>
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<p> CharT ch,<br /></p>
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<span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="sy1">=</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><span class="sy4">;</span></div>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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<td rowspan="142">(3)</td>
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="br0">(</span> <span class="kw4">const</span> basic_string<span class="sy3">&</span> other,<br /></span>
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<p> size_type pos,<br />
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size_type count <span class="sy1">=</span> <a href="cpp-string-basic_string-npos.html"><span class="kw1229">std::<span class="me2">basic_string</span><span class="sy4">::</span><span class="me2">npos</span></span></a>,<br /></p>
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<span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="sy1">=</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-until-cxx17">(C++17 前)</span></td>
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="br0">(</span> <span class="kw4">const</span> basic_string<span class="sy3">&</span> other,<br /></span>
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<p> size_type pos,<br /></p>
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<span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="sy1">=</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx17">(C++17 起)</span><br />
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<span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx20">
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> basic_string<span class="br0">(</span> <span class="kw4">const</span> basic_string<span class="sy3">&</span> other,<br /></span>
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<p> size_type pos,<br /></p>
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<span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="sy1">=</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><span class="sy4">;</span></div>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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<tbody></tbody>
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<tbody class="t-dcl-rev t-dcl-rev-num">
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<td rowspan="142">(3)</td>
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<tr class="t-dcl t-since-cxx17 t-until-cxx20">
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="br0">(</span> <span class="kw4">const</span> basic_string<span class="sy3">&</span> other,<br /></span>
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<p> size_type pos,<br />
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size_type count,<br /></p>
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<span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="sy1">=</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><span class="sy4">;</span></div>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx17">(C++17 起)</span><br />
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<span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
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<tr class="t-dcl t-since-cxx20">
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> basic_string<span class="br0">(</span> <span class="kw4">const</span> basic_string<span class="sy3">&</span> other,<br /></span>
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<p> size_type pos,<br />
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size_type count,<br /></p>
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<span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="sy1">=</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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<tbody class="t-dcl-rev t-dcl-rev-num">
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<td rowspan="142">(4)</td>
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="br0">(</span> <span class="kw4">const</span> CharT<span class="sy2">*</span> s,<br /></span>
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<p> size_type count,<br /></p>
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<span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="sy1">=</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx20">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> basic_string<span class="br0">(</span> <span class="kw4">const</span> CharT<span class="sy2">*</span> s,<br /></span>
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<p> size_type count,<br /></p>
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<span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="sy1">=</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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</tr>
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</tbody>
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<tbody></tbody>
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<tbody class="t-dcl-rev t-dcl-rev-num">
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<td rowspan="142">(5)</td>
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<td></td>
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<tr class="t-dcl t-until-cxx20">
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<td>
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="br0">(</span> <span class="kw4">const</span> CharT<span class="sy2">*</span> s,<br />
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<span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="sy1">=</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx20">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> basic_string<span class="br0">(</span> <span class="kw4">const</span> CharT<span class="sy2">*</span> s,<br />
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<span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="sy1">=</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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</tbody>
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<td rowspan="142">(6)</td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> InputIt <span class="sy1">></span><br /></span>
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<p>basic_string<span class="br0">(</span> InputIt first, InputIt last,<br /></p>
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<span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="sy1">=</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><span class="sy4">;</span></div>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> InputIt <span class="sy1">></span><br /></span>
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<p><span class="kw4">constexpr</span> basic_string<span class="br0">(</span> InputIt first, InputIt last,<br /></p>
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<span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="sy1">=</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><span class="sy4">;</span></div>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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<td rowspan="142">(7)</td>
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="br0">(</span> <span class="kw4">const</span> basic_string<span class="sy3">&</span> other <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
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<tr class="t-dcl t-since-cxx20">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> basic_string<span class="br0">(</span> <span class="kw4">const</span> basic_string<span class="sy3">&</span> other <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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<td rowspan="142">(7)</td>
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="br0">(</span> <span class="kw4">const</span> basic_string<span class="sy3">&</span> other, <span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx20">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> basic_string<span class="br0">(</span> <span class="kw4">const</span> basic_string<span class="sy3">&</span> other, <span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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<td rowspan="142">(8)</td>
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="br0">(</span> basic_string<span class="sy3">&&</span> other <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
|
|
<span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx20">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> basic_string<span class="br0">(</span> basic_string<span class="sy3">&&</span> other <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
|
|
</tr>
|
|
</tbody>
|
|
<tbody></tbody>
|
|
<tbody class="t-dcl-rev t-dcl-rev-num">
|
|
<tr class="t-dcl-rev-aux">
|
|
<td></td>
|
|
<td rowspan="142">(8)</td>
|
|
<td></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11 t-until-cxx20">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp">basic_string<span class="br0">(</span> basic_string<span class="sy3">&&</span> other, <span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="br0">)</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
|
|
<span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx20">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> basic_string<span class="br0">(</span> basic_string<span class="sy3">&&</span> other, <span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="br0">)</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
|
|
</tr>
|
|
</tbody>
|
|
<tbody></tbody>
|
|
<tbody class="t-dcl-rev t-dcl-rev-num">
|
|
<tr class="t-dcl-rev-aux">
|
|
<td></td>
|
|
<td rowspan="142">(9)</td>
|
|
<td></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11 t-until-cxx20">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp">basic_string<span class="br0">(</span> <a href="cpp-utility-initializer_list.html"><span class="kw960">std::<span class="me2">initializer_list</span></span></a><span class="sy1"><</span>CharT<span class="sy1">></span> ilist,<br />
|
|
<span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="sy1">=</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
|
|
<span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx20">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> basic_string<span class="br0">(</span> <a href="cpp-utility-initializer_list.html"><span class="kw960">std::<span class="me2">initializer_list</span></span></a><span class="sy1"><</span>CharT<span class="sy1">></span> ilist,<br />
|
|
<span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="sy1">=</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
|
|
</tr>
|
|
</tbody>
|
|
<tbody></tbody>
|
|
<tbody class="t-dcl-rev t-dcl-rev-num">
|
|
<tr class="t-dcl-rev-aux">
|
|
<td></td>
|
|
<td rowspan="142">(10)</td>
|
|
<td></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> T <span class="sy1">></span><br />
|
|
<span class="kw1">explicit</span> basic_string<span class="br0">(</span> <span class="kw4">const</span> T<span class="sy3">&</span> t, <span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="sy1">=</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><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-rev t-until-cxx20">(C++20 前)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx20">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span> <span class="sy1"><</span> <span class="kw1">class</span> T <span class="sy1">></span><br /></span>
|
|
<p><span class="kw1">explicit</span> <span class="kw4">constexpr</span> basic_string<span class="br0">(</span> <span class="kw4">const</span> T<span class="sy3">&</span> t,<br /></p>
|
|
<span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="sy1">=</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
|
|
</tr>
|
|
</tbody>
|
|
<tbody></tbody>
|
|
<tbody class="t-dcl-rev t-dcl-rev-num">
|
|
<tr class="t-dcl-rev-aux">
|
|
<td></td>
|
|
<td rowspan="142">(11)</td>
|
|
<td></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> T <span class="sy1">></span><br /></span>
|
|
<p>basic_string<span class="br0">(</span> <span class="kw4">const</span> T<span class="sy3">&</span> t, size_type pos, size_type n,<br /></p>
|
|
<span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="sy1">=</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><span class="sy4">;</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-rev t-until-cxx20">(C++20 前)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx20">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span> <span class="sy1"><</span> <span class="kw1">class</span> T <span class="sy1">></span><br /></span>
|
|
<p><span class="kw4">constexpr</span> basic_string<span class="br0">(</span> <span class="kw4">const</span> T<span class="sy3">&</span> t, size_type pos, size_type n,<br /></p>
|
|
<span class="kw4">const</span> Allocator<span class="sy3">&</span> alloc <span class="sy1">=</span> Allocator<span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
|
|
</tr>
|
|
</tbody>
|
|
<tbody>
|
|
<tr class="t-dcl t-since-cxx23">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> basic_string<span class="br0">(</span> <a href="cpp-types-nullptr_t.html"><span class="kw102">std::<span class="me2">nullptr_t</span></span></a> <span class="br0">)</span> <span class="sy1">=</span> delete<span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(12)</td>
|
|
<td><span class="t-mark-rev t-since-cxx23">(C++23 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl-sep">
|
|
<td></td>
|
|
<td></td>
|
|
<td></td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>从各种数据源构造新 string ，可选地使用用户提供的分配器 <code>alloc</code> 。</p>
|
|
<div class="t-li1"><span class="t-li">1)</span> 默认构造函数。构造空 string （拥有零大小和未指定的容量）。若不提供分配器，则从默认构造的实例获得分配器。</div>
|
|
<div class="t-li1"><span class="t-li">2)</span> 构造拥有字符 <code>ch</code> 的 <code>count</code> 个副本的 string 。<span class="t-rev-inl t-since-cxx17"><span>若会推导出不足以作为分配器的 <code>Allocator</code> 类型，则此构造函数不用于<a href="cpp-language-class_template_argument_deduction.html">类模板实参推导</a>。</span> <span><span class="t-mark-rev t-since-cxx17">(C++17 起)</span></span></span></div>
|
|
<div class="t-li1"><span class="t-li">3)</span> 以 <code>other</code> 的子串 <code>[pos, pos+count)</code> 构造 string 。若 <span class="t-c"><span class="mw-geshi cpp source-cpp">count <span class="sy1">==</span> npos</span></span> 或未指定 <code>count</code> ，或若请求的子串越过字符串的结尾，则产生的子串为 <code>[pos, other.size())</code> 。</div>
|
|
<div class="t-li1"><span class="t-li">4)</span> 以 <code>s</code> 所指向的字符串的首 <code>count</code> 个字符构造 string 。 <code>s</code> 能包含空字符。 string 的长度为 <code>count</code> 。若 <code>[s, s + count)</code> 不是合法范围则行为未定义。</div>
|
|
<div class="t-li1"><span class="t-li">5)</span> 以 <code>s</code> 所指向的空终止字符串的副本所初始化的内容构造 string 。以首个空字符确定字符串的长度。若 <code>[s, s + Traits::length(s))</code> 不是合法范围（例如若 <code>s</code> 是空指针）则行为未定义。<span class="t-rev-inl t-since-cxx17"><span>若会推导出不足以作为分配器的 <code>Allocator</code> 类型，则此构造函数不用于<a href="cpp-language-class_template_argument_deduction.html">类模板实参推导</a>。</span> <span><span class="t-mark-rev t-since-cxx17">(C++17 起)</span></span></span></div>
|
|
<div class="t-li1"><span class="t-li">6)</span> 构造拥有范围 <code>[first, last)</code> 内容的 string 。
|
|
<table class="t-rev-begin">
|
|
<tr class="t-rev t-until-cxx11">
|
|
<td>
|
|
<p>若 <code>InputIt</code> 为整数类型，则等价于 <code>basic_string(static_cast<size_type>(first), static_cast<value_type>(last), a)</code> 。</p>
|
|
</td>
|
|
<td><span class="t-mark-rev t-until-cxx11">(C++11 前)</span></td>
|
|
</tr>
|
|
<tr class="t-rev t-since-cxx11">
|
|
<td>
|
|
<p>此构造函数仅若 <code>InputIt</code> 满足 <a href="cpp-named_req-InputIterator.html"><span style="font-style:italic">老式输入迭代器</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(LegacyInputIterator)</span></a> 才参与重载决议。</p>
|
|
</td>
|
|
<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
|
|
</tr>
|
|
</table>
|
|
</div>
|
|
<div class="t-li1"><span class="t-li">7)</span> 复制构造函数。构造拥有 <code>other</code> 内容副本的 string 。</div>
|
|
<div class="t-li1"><span class="t-li">8)</span> 移动构造函数。用移动语义构造拥有 <code>other</code> 内容的 string 。将 <code>other</code> 留在合法但未指定的状态。</div>
|
|
<div class="t-li1"><span class="t-li">9)</span> 构造拥有 initializer_list <code>ilist</code> 内容的 string 。</div>
|
|
<div class="t-li1"><span class="t-li">10)</span> 如同用 <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-string-basic_string_view.html"><span class="kw1246">std::<span class="me2">basic_string_view</span></span></a><span class="sy1"><</span>CharT, Traits<span class="sy1">></span> sv <span class="sy1">=</span> t<span class="sy4">;</span></span></span> 隐式转换 <code>t</code> 为 string_view <code>sv</code> ，然后如同用 <span class="t-c"><span class="mw-geshi cpp source-cpp">basic_string<span class="br0">(</span>sv.<span class="me1">data</span><span class="br0">(</span><span class="br0">)</span>, sv.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span>, alloc<span class="br0">)</span></span></span> ，以 <code>sv</code> 的内容初始化 string 。此重载仅若 <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-types-is_convertible.html"><span class="kw593">std::<span class="me2">is_convertible_v</span></span></a><span class="sy1"><</span><span class="kw4">const</span> T<span class="sy3">&</span>, <a href="cpp-string-basic_string_view.html"><span class="kw1246">std::<span class="me2">basic_string_view</span></span></a><span class="sy1"><</span>CharT, Traits<span class="sy1">>></span></span></span> 为 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> 且 <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-types-is_convertible.html"><span class="kw593">std::<span class="me2">is_convertible_v</span></span></a><span class="sy1"><</span><span class="kw4">const</span> T<span class="sy3">&</span>, <span class="kw4">const</span> CharT<span class="sy2">*</span><span class="sy1">></span></span></span> 为 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">false</span></span></span> 才参与重载决议。</div>
|
|
<div class="t-li1"><span class="t-li">11)</span> 如同用 <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-string-basic_string_view.html"><span class="kw1246">std::<span class="me2">basic_string_view</span></span></a><span class="sy1"><</span>CharT, Traits<span class="sy1">></span> sv <span class="sy1">=</span> t<span class="sy4">;</span></span></span> 隐式转换 <code>t</code> 为 string_view <code>sv</code> ，然后如同用 <span class="t-c"><span class="mw-geshi cpp source-cpp">basic_string<span class="br0">(</span>sv.<span class="me1">substr</span><span class="br0">(</span>pos, n<span class="br0">)</span>, a<span class="br0">)</span></span></span> ，以 <code>sv</code> 的子范围 <code>[pos, pos + n)</code> 初始化 string 。此重载仅若 <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-types-is_convertible.html"><span class="kw593">std::<span class="me2">is_convertible_v</span></span></a><span class="sy1"><</span><span class="kw4">const</span> T<span class="sy3">&</span>, <a href="cpp-string-basic_string_view.html"><span class="kw1246">std::<span class="me2">basic_string_view</span></span></a><span class="sy1"><</span>CharT, Traits<span class="sy1">>></span></span></span> 为 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> 才参与重载决议。</div>
|
|
<div class="t-li1"><span class="t-li">12)</span> 不能从 <span class="t-c"><span class="mw-geshi cpp source-cpp">nullptr</span></span> 构造 <code>basic_string</code> 。</div>
|
|
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">参数</span></h3>
|
|
<table class="t-par-begin">
|
|
<tr class="t-par">
|
|
<td>alloc</td>
|
|
<td>-</td>
|
|
<td>用于此 string 所有内存分配的分配器</td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td>count</td>
|
|
<td>-</td>
|
|
<td>产生的 string 大小</td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td>ch</td>
|
|
<td>-</td>
|
|
<td>初始化 string 所用的值</td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td>pos</td>
|
|
<td>-</td>
|
|
<td>要包含的首字符位置</td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td>first, last</td>
|
|
<td>-</td>
|
|
<td>复制字符的来源范围</td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td>s</td>
|
|
<td>-</td>
|
|
<td>指向用作源初始化 string 的字符数组的指针</td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td>other</td>
|
|
<td>-</td>
|
|
<td>用作源初始化 string 的另一 string</td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td>ilist</td>
|
|
<td>-</td>
|
|
<td>初始化 string 所用的 <span class="t-lc"><a href="cpp-utility-initializer_list.html">std::initializer_list</a></span></td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td>t</td>
|
|
<td>-</td>
|
|
<td>初始化 string 所用的对象（可转换为 <span class="t-lc"><a href="cpp-string-basic_string_view.html">std::basic_string_view</a></span> ）</td>
|
|
</tr>
|
|
</table>
|
|
<h3><span class="mw-headline" id=".E5.A4.8D.E6.9D.82.E5.BA.A6">复杂度</span></h3>
|
|
<div class="t-li1"><span class="t-li">1)</span> 常数</div>
|
|
<div class="t-li1"><span class="t-li">2-4)</span> 与 <code>count</code> 成线性</div>
|
|
<div class="t-li1"><span class="t-li">5)</span> 与 <code>s</code> 的长度成线性</div>
|
|
<div class="t-li1"><span class="t-li">6)</span> 与 <code>first</code> 和 <code>last</code> 间的距离成线性</div>
|
|
<div class="t-li1"><span class="t-li">7)</span> 与 <code>other</code> 的大小成线性</div>
|
|
<div class="t-li1"><span class="t-li">8)</span> 常数。若给出 <code>alloc</code> 且 <span class="t-c"><span class="mw-geshi cpp source-cpp">alloc <span class="sy3">!</span><span class="sy1">=</span> other.<span class="me1">get_allocator</span><span class="br0">(</span><span class="br0">)</span></span></span> 则为线性</div>
|
|
<div class="t-li1"><span class="t-li">9)</span> 与 <code>ilist</code> 的大小成线性</div>
|
|
<h3><span class="mw-headline" id=".E5.BC.82.E5.B8.B8">异常</span></h3>
|
|
<div class="t-li1"><span class="t-li">3)</span> 若 <span class="t-c"><span class="mw-geshi cpp source-cpp">pos <span class="sy1">></span> other.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span></span></span> 则为 <span class="t-lc"><a href="cpp-error-out_of_range.html">std::out_of_range</a></span></div>
|
|
<div class="t-li1"><span class="t-li">8)</span> 若 <span class="t-c"><span class="mw-geshi cpp source-cpp">alloc <span class="sy1">==</span> str.<span class="me1">get_allocator</span><span class="br0">(</span><span class="br0">)</span></span></span> 则不抛出</div>
|
|
<div class="t-li1"><span class="t-li">11)</span> 若 <span class="t-c"><span class="mw-geshi cpp source-cpp">pos</span></span> 在范围外则为 <span class="t-lc"><a href="cpp-error-out_of_range.html">std::out_of_range</a></span></div>
|
|
<p>若构造的字符串长度会超出 <span class="t-lc"><a href="cpp-string-basic_string-max_size.html">max_size()</a></span> （例如对于 <span class="t-v">(2)</span> ，若 <span class="t-c"><span class="mw-geshi cpp source-cpp">count <span class="sy1">></span> max_size<span class="br0">(</span><span class="br0">)</span></span></span> ）则抛出 <span class="t-lc"><a href="cpp-error-length_error.html">std::length_error</a></span> 。调用 <code>Allocator::allocate</code> 可能抛出。</p>
|
|
<h3><span class="mw-headline" id=".E6.B3.A8.E6.84.8F">注意</span></h3>
|
|
<p>以含内嵌 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">'<span class="es5">\0</span>'</span></span></span> 字符的<a href="cpp-language-string_literal.html">字符串字面量</a>初始化 string 会使用重载 <span class="t-v">(5)</span> ，并在首个空字符停止。这可通过指定不同的构造函数，或通过使用 <a href="cpp-string-basic_string-operator_22_22s.html"><code>operator""s</code></a> 避免：</p>
|
|
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
|
<div class="cpp source-cpp">
|
|
<pre class="de1"><a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> s1 <span class="sy1">=</span> <span class="st0">"ab<span class="es5">\0</span><span class="es5">\0</span>cd"</span><span class="sy4">;</span> <span class="co1">// s1 含 "ab"</span>
|
|
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> s2<span class="br0">{</span><span class="st0">"ab<span class="es5">\0</span><span class="es5">\0</span>cd"</span>, <span class="nu0">6</span><span class="br0">}</span><span class="sy4">;</span> <span class="co1">// s2 含 "ab\0\0cd"</span>
|
|
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> s3 <span class="sy1">=</span> <span class="st0">"ab<span class="es5">\0</span><span class="es5">\0</span>cd"</span>s<span class="sy4">;</span> <span class="co1">// s3 含 "ab\0\0cd"</span></pre></div>
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</div>
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<h3><span class="mw-headline" id=".E7.BC.BA.E9.99.B7.E6.8A.A5.E5.91.8A">缺陷报告</span></h3>
|
|
<p>下列更改行为的缺陷报告追溯地应用于以前出版的 C++ 标准。</p>
|
|
<table class="dsctable" style="font-size:0.8em">
|
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<tr>
|
|
<th>DR</th>
|
|
<th>应用于</th>
|
|
<th>出版时的行为</th>
|
|
<th>正确行为</th>
|
|
</tr>
|
|
<tr>
|
|
<td><a rel="nofollow" class="external text" href="https://cplusplus.github.io/LWG/issue2193">LWG 2193</a></td>
|
|
<td>C++11</td>
|
|
<td>默认构造函数为 explicit</td>
|
|
<td>使之为非 explicit</td>
|
|
</tr>
|
|
<tr>
|
|
<td><a rel="nofollow" class="external text" href="https://cplusplus.github.io/LWG/issue2946">LWG 2946</a></td>
|
|
<td>C++17</td>
|
|
<td><code>string_view</code> 重载在一些情况下导致歧义</td>
|
|
<td>通过使之为模板来避免</td>
|
|
</tr>
|
|
<tr>
|
|
<td><a rel="nofollow" class="external text" href="https://cplusplus.github.io/LWG/issue3076">LWG 3076</a></td>
|
|
<td>C++17</td>
|
|
<td>二个构造函数可能在类模板实参推导中导致歧义</td>
|
|
<td>已制约</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 <cassert></span>
|
|
<span class="co2">#include <iterator></span>
|
|
<span class="co2">#include <string></span>
|
|
<span class="co2">#include <cctype></span>
|
|
|
|
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
|
|
<span class="br0">{</span>
|
|
<span class="br0">{</span>
|
|
<span class="co1">// string::string()</span>
|
|
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> s<span class="sy4">;</span>
|
|
<a href="cpp-error-assert.html"><span class="kw774">assert</span></a><span class="br0">(</span>s.<span class="me1">empty</span><span class="br0">(</span><span class="br0">)</span> <span class="sy3">&&</span> <span class="br0">(</span>s.<span class="me1">length</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1">==</span> <span class="nu0">0</span><span class="br0">)</span> <span class="sy3">&&</span> <span class="br0">(</span>s.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1">==</span> <span class="nu0">0</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
|
|
<span class="br0">}</span>
|
|
|
|
<span class="br0">{</span>
|
|
<span class="co1">// string::string(size_type count, charT ch)</span>
|
|
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> s<span class="br0">(</span><span class="nu0">4</span>, <span class="st0">'='</span><span class="br0">)</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"><<</span> s <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span> <span class="co1">// "===="</span>
|
|
<span class="br0">}</span>
|
|
|
|
<span class="br0">{</span>
|
|
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> <span class="kw4">const</span> other<span class="br0">(</span><span class="st0">"Exemplary"</span><span class="br0">)</span><span class="sy4">;</span>
|
|
<span class="co1">// string::string(string const& other, size_type pos, size_type count)</span>
|
|
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> s<span class="br0">(</span>other, <span class="nu0">0</span>, other.<span class="me1">length</span><span class="br0">(</span><span class="br0">)</span><span class="sy2">-</span><span class="nu0">1</span><span class="br0">)</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"><<</span> s <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span> <span class="co1">// "Exemplar"</span>
|
|
<span class="br0">}</span>
|
|
|
|
<span class="br0">{</span>
|
|
<span class="co1">// string::string(charT const* s, size_type count)</span>
|
|
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> s<span class="br0">(</span><span class="st0">"C-style string"</span>, <span class="nu0">7</span><span class="br0">)</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"><<</span> s <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span> <span class="co1">// "C-style"</span>
|
|
<span class="br0">}</span>
|
|
|
|
<span class="br0">{</span>
|
|
<span class="co1">// string::string(charT const* s)</span>
|
|
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> s<span class="br0">(</span><span class="st0">"C-style<span class="es5">\0</span>string"</span><span class="br0">)</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"><<</span> s <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span> <span class="co1">// "C-style"</span>
|
|
<span class="br0">}</span>
|
|
|
|
<span class="br0">{</span>
|
|
<span class="kw4">char</span> mutable_c_str<span class="br0">[</span><span class="br0">]</span> <span class="sy1">=</span> <span class="st0">"another C-style string"</span><span class="sy4">;</span>
|
|
<span class="co1">// string::string(InputIt first, InputIt last)</span>
|
|
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> s<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>mutable_c_str<span class="br0">)</span><span class="sy2">+</span><span class="nu0">8</span>, <a href="cpp-iterator-end.html"><span class="kw680">std::<span class="me2">end</span></span></a><span class="br0">(</span>mutable_c_str<span class="br0">)</span><span class="sy2">-</span><span class="nu0">1</span><span class="br0">)</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"><<</span> s <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span> <span class="co1">// "C-style string"</span>
|
|
<span class="br0">}</span>
|
|
|
|
<span class="br0">{</span>
|
|
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> <span class="kw4">const</span> other<span class="br0">(</span><span class="st0">"Exemplar"</span><span class="br0">)</span><span class="sy4">;</span>
|
|
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> s<span class="br0">(</span>other<span class="br0">)</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"><<</span> s <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span> <span class="co1">// "Exemplar"</span>
|
|
<span class="br0">}</span>
|
|
|
|
<span class="br0">{</span>
|
|
<span class="co1">// string::string(string&& str)</span>
|
|
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> s<span class="br0">(</span><a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a><span class="br0">(</span><span class="st0">"C++ by "</span><span class="br0">)</span> <span class="sy2">+</span> <a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a><span class="br0">(</span><span class="st0">"example"</span><span class="br0">)</span><span class="br0">)</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"><<</span> s <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span> <span class="co1">// "C++ by example"</span>
|
|
<span class="br0">}</span>
|
|
|
|
<span class="br0">{</span>
|
|
<span class="co1">// string(std::initializer_list<charT> ilist)</span>
|
|
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> s<span class="br0">(</span><span class="br0">{</span> <span class="st0">'C'</span>, <span class="st0">'-'</span>, <span class="st0">'s'</span>, <span class="st0">'t'</span>, <span class="st0">'y'</span>, <span class="st0">'l'</span>, <span class="st0">'e'</span> <span class="br0">}</span><span class="br0">)</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"><<</span> s <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span> <span class="co1">// "C-style"</span>
|
|
<span class="br0">}</span>
|
|
|
|
<span class="br0">{</span>
|
|
<span class="co1">// 重载决议选择 string(InputIt first, InputIt last) [with InputIt = int]</span>
|
|
<span class="co1">// 这表现为如同调用 string(size_type count, charT ch)</span>
|
|
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> s<span class="br0">(</span><span class="nu0">3</span>, std<span class="sy4">::</span><span class="me2">toupper</span><span class="br0">(</span><span class="st0">'a'</span><span class="br0">)</span><span class="br0">)</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"><<</span> s <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span> <span class="co1">// "AAA"</span>
|
|
<span class="br0">}</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">====
|
|
Exemplar
|
|
C-style
|
|
C-style
|
|
C-style string
|
|
Exemplar
|
|
C++ by example
|
|
C-style
|
|
AAA</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-string-basic_string-assign.html"><span class="t-lines"><span>assign</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>赋值字符给字符串<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-string-basic_string-operator=.html"><span class="t-lines"><span>operator=</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>为字符串赋值<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-string-basic_string-to_string.html"><span class="t-lines"><span>to_string</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>转换整数或浮点值为 <code>string</code><br />
|
|
<span class="t-mark">(函数)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-string-basic_string-to_wstring.html"><span class="t-lines"><span>to_wstring</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>转换整数或浮点值为 <code>wstring</code><br />
|
|
<span class="t-mark">(函数)</span></td>
|
|
</tr>
|
|
</table>
|
|
</div>
|
|
<div class="visualClear"></div>
|
|
</div>
|
|
</div>
|
|
</div>
|
|
</body>
|
|
</html>
|