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<title>Issue 2590: Aggregate initialization for std::array</title>
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<p><em>This page is a snapshot from the LWG issues list, see the <a href="lwg-active.html">Library Active Issues List</a> for more information and the meaning of <a href="lwg-active.html#C++17">C++17</a> status.</em></p>
<h3 id="2590"><a href="lwg-defects.html#2590">2590</a>. Aggregate initialization for <code>std::array</code></h3>
<p><b>Section:</b> 23.3.3.1 <a href="https://wg21.link/array.overview">[array.overview]</a> <b>Status:</b> <a href="lwg-active.html#C++17">C++17</a>
 <b>Submitter:</b> Robert Haberlach <b>Opened:</b> 2016-01-30 <b>Last modified:</b> 2017-07-30</p>
<p><b>Priority: </b>0
</p>
<p><b>View other</b> <a href="lwg-index-open.html#array.overview">active issues</a> in [array.overview].</p>
<p><b>View all other</b> <a href="lwg-index.html#array.overview">issues</a> in [array.overview].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#C++17">C++17</a> status.</p>
<p><b>Discussion:</b></p>
<p>
Similar to <a href="http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#1270">core issue 1270's</a> resolution, 
23.3.3.1 <a href="https://wg21.link/array.overview">[array.overview]</a>/2 should cover aggregate-initialization in general. 
As it stands, that paragraph solely mentions copy-list-initialization &mdash; i.e. it is unclear whether the following 
notation is (guaranteed to be) well-formed:
</p>
<blockquote><pre>
std::array&lt;int, 1&gt; arr{0};
</pre></blockquote>

<p><i>[2016-02, Issues Telecon]</i></p>

<p>
P0; move to Tentatively Ready.
</p>


<p id="res-2590"><b>Proposed resolution:</b></p>
<p>
This wording is relative to N4567.
</p>

<ol>
<li><p>Change 23.3.3.1 <a href="https://wg21.link/array.overview">[array.overview]</a> p2 as indicated:</p>
<blockquote><p>
-2- An <code>array</code> is an aggregate (8.5.1) that can be <ins>list-</ins>initialized with <del>the syntax</del>
</p>
<blockquote><pre>
<del>array&lt;T, N&gt; a = { <i>initializer-list</i> };</del>
</pre></blockquote>
<p>
<del>where <i>initializer-list</i> is a comma-separated list of</del> up to <code>N</code> elements whose types are convertible to <code>T</code>.
</p>
</blockquote>
</li>
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