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<title>Issue 2829: LWG 2740 leaves behind vacuous words</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#Open">Open</a> status.</em></p>
<h3 id="2829"><a href="lwg-active.html#2829">2829</a>. LWG 2740 leaves behind vacuous words</h3>
<p><b>Section:</b> 22.5.3.7 <a href="https://wg21.link/optional.observe">[optional.observe]</a> <b>Status:</b> <a href="lwg-active.html#Open">Open</a>
 <b>Submitter:</b> Richard Smith <b>Opened:</b> 2016-11-24 <b>Last modified:</b> 2020-06-13</p>
<p><b>Priority: </b>2
</p>
<p><b>View other</b> <a href="lwg-index-open.html#optional.observe">active issues</a> in [optional.observe].</p>
<p><b>View all other</b> <a href="lwg-index.html#optional.observe">issues</a> in [optional.observe].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#Open">Open</a> status.</p>
<p><b>Discussion:</b></p>
<p>
After applying LWG <a href="lwg-defects.html#2740" title="constexpr optional&lt;T&gt;::operator-&gt; (Status: C++17)">2740</a><sup><a href="https://cplusplus.github.io/LWG/issue2740" title="Latest snapshot">(i)</a></sup>, we have:
</p>
<blockquote>
<pre>
constexpr const T* operator-&gt;() const;
constexpr T* operator-&gt;();
</pre>
<blockquote>
<p>
-1- <i>Requires:</i> <code>*this</code> contains a value.
<p/>
-2- <i>Returns:</i> <code>val</code>.
<p/>
-3- <i>Throws:</i> Nothing.
<p/>
-4- <i>Remarks:</i> These functions shall be <code>constexpr</code> functions.
</p>
</blockquote>
</blockquote>
<p>
Paragraph 4 is completely superfluous. We already said these functions were <code>constexpr</code> in the synopsis. Can it be removed?
</p>

<p><i>[Issues Telecon 16-Dec-2016]</i></p>

<p>Priority 2</p>
<p>Jonathan notes: Although Richard is correct, I suggest we don't strike the paragraph, so that we 
remember to fix it as part of <a href="lwg-active.html#2833" title="Library needs to specify what it means when it declares a function constexpr (Status: Open)">2833</a><sup><a href="https://cplusplus.github.io/LWG/issue2833" title="Latest snapshot">(i)</a></sup>, when we know how to say
this properly.</p>

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

<p>Status to Open; also see 7.7 <a href="https://wg21.link/expr.const">[expr.const]</a>/6 and <a href="lwg-active.html#2289" title="constexpr guarantees of defaulted functions still insufficient (Status: Open)">2289</a><sup><a href="https://cplusplus.github.io/LWG/issue2289" title="Latest snapshot">(i)</a></sup>.</p>

<p><i>[2020-06-08 Nina Dinka Ranns comments]</i></p>

<p>
The revised wording provided by LWG <a href="lwg-active.html#2833" title="Library needs to specify what it means when it declares a function constexpr (Status: Open)">2833</a><sup><a href="https://cplusplus.github.io/LWG/issue2833" title="Latest snapshot">(i)</a></sup> should resolve this issue as well.
</p>


<p id="res-2829"><b>Proposed resolution:</b></p>





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