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<title>Issue 1386: pack_arguments overly complex</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++11">C++11</a> status.</em></p>
<h3 id="1386"><a href="lwg-defects.html#1386">1386</a>. <code>pack_arguments</code> overly complex</h3>
<p><b>Section:</b> 22.4.5 <a href="https://wg21.link/tuple.creation">[tuple.creation]</a> <b>Status:</b> <a href="lwg-active.html#C++11">C++11</a>
 <b>Submitter:</b> INCITS <b>Opened:</b> 2010-08-25 <b>Last modified:</b> 2016-01-28</p>
<p><b>Priority: </b>Not Prioritized
</p>
<p><b>View all other</b> <a href="lwg-index.html#tuple.creation">issues</a> in [tuple.creation].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#C++11">C++11</a> status.</p>
<p><b>Discussion:</b></p>
<p><b>Addresses US-99</b></p>
<p>
<code>pack_arguments</code> is overly complex.
</p>

<p><i>[
Resolved in Rapperswil by a motion to directly apply the words from the ballot comment in N3102.
]</i></p>




<p id="res-1386"><b>Proposed resolution:</b></p><p>
This issue resulted from a lack of understanding of
how references are forwarded. The definition of
<code>pack_arguments</code> should be simply:<br/>
<code>template &lt;class... Types&gt;
tuple&lt;<del>A</del>Types<ins>&amp;&amp;</ins>&gt;
pack_arguments(Types&amp;&amp;...t);</code><br/>
<del>Types: Let <code>Ti</code> be each type in <code>Types</code>....</del><br/>
<i>Effects</i>: ...<br/>
<i>Returns</i>:<br/>
<code>tuple&lt;<del>A</del>Types<ins>&amp;&amp;</ins>...&gt;(std::forward&lt;Types&gt;(t)...)</code><br/>
The synopsis should also change to reflect this simpler signature.
</p>




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