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<title>Issue 2285: make_reverse_iterator</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++14">C++14</a> status.</em></p>
<h3 id="2285"><a href="lwg-defects.html#2285">2285</a>. <code>make_reverse_iterator</code></h3>
<p><b>Section:</b> 24.5.1 <a href="https://wg21.link/reverse.iterators">[reverse.iterators]</a> <b>Status:</b> <a href="lwg-active.html#C++14">C++14</a>
 <b>Submitter:</b> Zhihao Yuan <b>Opened:</b> 2013-08-27 <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#reverse.iterators">issues</a> in [reverse.iterators].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#C++14">C++14</a> status.</p>
<p><b>Discussion:</b></p>
<p>
We have <code>make_move_iterator</code>, but not <code>make_reverse_iterator</code>, which
is also useful when dealing with some types without an <code>rbegin</code>/<code>rend</code> support (like, C strings).
</p>

<p><i>[2013-09 Chicago]</i></p>

<p>
Billy: reviewed it last night STL: has suggested prior, but denied for complexity 
<p/>
Billy: Alisdair wanted to review for <code>reverse(reverse())</code>; 
<p/>
STL: likes the issue, was like him 
<p/>
Stefanus: likes definitions, places where things should be 
<p/>
STL: for consistency with <code>make_move_iterator</code> 
<p/>
Stefanus: minor editorial issue - subdivision in these 2 sections is different from  [move.iter]. 
See 24.5.4.9 <a href="https://wg21.link/move.iter.nonmember">[move.iter.nonmember]</a>
<p/>
STL: motion to move to Ready
<p/>
Move to Ready 
</p>



<p id="res-2285"><b>Proposed resolution:</b></p>
<p>This wording is relative to N3691.</p>

<ol>
<li><p>Change header <code>&lt;iterator&gt;</code> synopsis, 24.2 <a href="https://wg21.link/iterator.synopsis">[iterator.synopsis]</a> as indicated:</p>

<blockquote>
<pre>
namespace std {
  [&hellip;]
  template &lt;class Iterator&gt;
    reverse_iterator&lt;Iterator&gt; operator+(
      typename reverse_iterator&lt;Iterator&gt;::difference_type n,
      const reverse_iterator&lt;Iterator>&amp; x);
<ins>
  template &lt;class Iterator&gt;
    reverse_iterator&lt;Iterator&gt; make_reverse_iterator(Iterator i);
</ins>
}
</pre>
</blockquote>
</li>

<li><p>Change class template <code>reverse_iterator</code> synopsis, 24.5.1.2 <a href="https://wg21.link/reverse.iterator">[reverse.iterator]</a> as indicated:</p>

<blockquote>
<pre>
namespace std {
  [&hellip;]
  template &lt;class Iterator&gt;
    reverse_iterator&lt;Iterator&gt; operator+(
      typename reverse_iterator&lt;Iterator&gt;::difference_type n,
      const reverse_iterator&lt;Iterator>&amp; x);
<ins>
  template &lt;class Iterator&gt;
    reverse_iterator&lt;Iterator&gt; make_reverse_iterator(Iterator i);
</ins>
}
</pre>
</blockquote>
</li>

<li><p>After  [reverse.iter.opsum] add the following new sub-clause to  [reverse.iter.ops]:</p>

<blockquote>
<pre>
<ins>
template &lt;class Iterator&gt;
  reverse_iterator&lt;Iterator&gt; make_reverse_iterator(Iterator i);
</ins>
</pre><blockquote>
<p>
<ins>-?- <i>Returns:</i> <code>reverse_iterator&lt;Iterator&gt;(i)</code>.</ins>
</p>
</blockquote></blockquote>
</li>

</ol>





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