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<title>Issue 3491: What is a "decayed type"?</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#New">New</a> status.</em></p>
<h3 id="3491"><a href="lwg-active.html#3491">3491</a>. What is a "decayed type"?</h3>
<p><b>Section:</b> 17.12.6 <a href="https://wg21.link/cmp.alg">[cmp.alg]</a>, 25.7.6.1 <a href="https://wg21.link/range.all.general">[range.all.general]</a>, 17.12.6 <a href="https://wg21.link/cmp.alg">[cmp.alg]</a> <b>Status:</b> <a href="lwg-active.html#New">New</a>
 <b>Submitter:</b> Alisdair Meredith <b>Opened:</b> 2020-10-27 <b>Last modified:</b> 2021-10-30</p>
<p><b>Priority: </b>3
</p>
<p><b>View other</b> <a href="lwg-index-open.html#cmp.alg">active issues</a> in [cmp.alg].</p>
<p><b>View all other</b> <a href="lwg-index.html#cmp.alg">issues</a> in [cmp.alg].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#New">New</a> status.</p>
<p><b>Discussion:</b></p>
<p>
Some of our newer wording for C++20 uses the term "decayed type" as if it were 
a defined term of art.  While I have intuition for what may be intended in these 
cases, it turns out the "function to function pointer decay" and "array to array 
pointer decay" were never actually Core terms of art &mdash; having searched all
standards going back as far as C++03.
<p/>
We should either define this term for library use, or find a way to state
our intent using existing well-defined terms of art.
<p/>
Affected clauses:
<p/>
<ul>
<li><p>17.12.6 <a href="https://wg21.link/cmp.alg">[cmp.alg]</a>: Most heavily used here.</p></li>
<li><p>25.7.6.1 <a href="https://wg21.link/range.all.general">[range.all.general]</a></p></li>
<li><p>17.12.6 <a href="https://wg21.link/cmp.alg">[cmp.alg]</a></p></li>
</ul>
</p>

<p><i>[2021-01-15; Telecon prioritization]</i></p>

<p>
Set priority to 3 following reflector and telecon discussions.
</p>



<p id="res-3491"><b>Proposed resolution:</b></p>





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