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<title>Issue 2780: basic_string_view::copy is missing constexpr</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#Resolved">Resolved</a> status.</em></p>
<h3 id="2780"><a href="lwg-defects.html#2780">2780</a>. <code>basic_string_view::copy</code> is missing <code>constexpr</code></h3>
<p><b>Section:</b> 27.3 <a href="https://wg21.link/string.view">[string.view]</a> <b>Status:</b> <a href="lwg-active.html#Resolved">Resolved</a>
 <b>Submitter:</b> Billy Robert O'Neal III <b>Opened:</b> 2016-10-07 <b>Last modified:</b> 2018-11-25</p>
<p><b>Priority: </b>2
</p>
<p><b>View other</b> <a href="lwg-index-open.html#string.view">active issues</a> in [string.view].</p>
<p><b>View all other</b> <a href="lwg-index.html#string.view">issues</a> in [string.view].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#Resolved">Resolved</a> status.</p>
<p><b>Discussion:</b></p>
<p>
Now that we have C++14 relaxed <code>constexpr</code>, we can also take care
of the assignment operator and <code>copy</code>.
</p>
<p><i>[Issues processing Telecon 2016-10-07]</i></p>

<p>Split off from <a href="lwg-defects.html#2778" title="basic_string_view is missing constexpr (Status: C++17)">2778</a><sup><a href="https://cplusplus.github.io/LWG/issue2778" title="Latest snapshot">(i)</a></sup></p>

<p><i>[2016-11-12, Issaquah]</i></p>

<p>Sat PM: Status LEWG</p>

<p><i>[LEWG Kona 2017]</i></p>

<p>Recommend NAD: Don't want to spend the committee time. Can call std::copy if you want this, after LEWG159 goes into C++20.</p>

<p><i>[2018-06 Rapperswil Wednesday issues processing]</i></p>

<p>This will be addressed by <a href="https://wg21.link/P1032">P1032</a>.</p>

<p>Resolved by the adoption of <a href="https://wg21.link/P1032">P1032</a> in San Diego.</p>


<p id="res-2780"><b>Proposed resolution:</b></p>
<p>
This wording is relative to N4606.
</p>

<ol>
<li><p>In 27.3.3 <a href="https://wg21.link/string.view.template">[string.view.template]</a>, add <code>constexpr</code> to <code>copy</code>:</p>

<blockquote>
<pre>
<ins>constexpr </ins>size_type copy(charT* s, size_type n, size_type pos = 0) const;
</pre>
</blockquote>
</li>

<li><p>In 27.3.3.8 <a href="https://wg21.link/string.view.ops">[string.view.ops]</a>, add <code>constexpr</code> to <code>copy</code>:</p>

<blockquote>
<pre>
<ins>constexpr </ins>size_type copy(charT* s, size_type n, size_type pos = 0) const;
</pre>
</blockquote>
</li>
</ol>






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