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<title>Issue 2925: Template argument deduction is not used in the standard library</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="2925"><a href="lwg-defects.html#2925">2925</a>. Template argument deduction is not used in the standard library</h3>
<p><b>Section:</b> 16 <a href="https://wg21.link/library">[library]</a> <b>Status:</b> <a href="lwg-active.html#Resolved">Resolved</a>
 <b>Submitter:</b> United States <b>Opened:</b> 2017-02-03 <b>Last modified:</b> 2020-09-06</p>
<p><b>Priority: </b>Not Prioritized
</p>
<p><b>View other</b> <a href="lwg-index-open.html#library">active issues</a> in [library].</p>
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<p><b>Discussion:</b></p>
<b>Addresses US 7</b>

<p><a href="https://wg21.link/p0091r3">P0091R3</a> "Template argument deduction for class templates (Rev. 6)" was adopted 
for the core language, but the Standard Library makes no explicit use of this new feature, even though the promise of 
such use provided strong motivation for the feature.</p>

<p>Proposed change: Analyze the Standard Library's constructors to determine which classes would profit from explicit 
deduction guides. Formulate the appropriate guides for those classes and insert them in their respective types.</p>

<p><i>[2017-02-03, Marshall notes]</i></p>

<p><a href="https://wg21.link/p0433">P0433</a> is an attempt to do exactly this.</p>

<p><i>[2017-03-12, post-Kona]</i></p>

<p>Resolved by P0433R2.</p>


<p id="res-2925"><b>Proposed resolution:</b></p>
<p>
</p>






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