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  <h1 itemprop="name"><span class="token">構造化束縛への属性を許可 [P0609R3]</span><span class="cpp cpp26" title="C++26で追加">(C++26)</span></h1>
<div itemprop="articleBody"><p>
</p>
<p>このページはC++26に採用される見込みの言語機能の変更を解説しています。</p>
<p>のちのC++規格でさらに変更される場合があるため<a href="#relative-page">関連項目</a>を参照してください。</p>
<p>
</p>
<h2>概要</h2>
<p>C++26では、構造化束縛の各要素に対して属性を指定できるようになる。</p>
<p><div class="codehilite"><pre><span></span><code><span class="c1">// 構造化束縛した変数bは使わない</span>
<span class="k">auto</span><span class="w"> </span><span class="p">[</span><span class="n">a</span><span class="p">,</span><span class="w"> </span><span class="n">b</span><span class="w"> </span><span class="p">[[</span><span class="n">maybe_unused</span><span class="p">]],</span><span class="w"> </span><span class="n">c</span><span class="p">]</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">f</span><span class="p">();</span>
</code></pre></div>
</p>
<p>構文としては、構造化束縛の要素となる変数名の後ろに属性を指定する。</p>
<h2><a href="#relative-page" id="relative-page">関連項目</a></h2>
<ul>
<li><a href="../cpp11/attributes.html">C++11 属性構文</a></li>
<li><a href="../cpp17/structured_bindings.html">C++17 構造化束縛</a></li>
</ul>
<h2>参照</h2>
<ul>
<li><a href="https://open-std.org/jtc1/sc22/wg21/docs/papers/2024/p0609r3.pdf" target="_blank">P0609R3 Attributes for Structured Bindings</a></li>
</ul></div>

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