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<title>Issue 1014: basic_regex should be created/assigned from initializer lists</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="1014"><a href="lwg-defects.html#1014">1014</a>. <code>basic_regex</code> should be created/assigned from initializer lists</h3>
<p><b>Section:</b> 28.6.7.2 <a href="https://wg21.link/re.regex.construct">[re.regex.construct]</a> <b>Status:</b> <a href="lwg-active.html#C++11">C++11</a>
 <b>Submitter:</b> Alisdair Meredith <b>Opened:</b> 2009-03-11 <b>Last modified:</b> 2016-01-28</p>
<p><b>Priority: </b>Not Prioritized
</p>
<p><b>View other</b> <a href="lwg-index-open.html#re.regex.construct">active issues</a> in [re.regex.construct].</p>
<p><b>View all other</b> <a href="lwg-index.html#re.regex.construct">issues</a> in [re.regex.construct].</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 UK 317 and JP 74</b></p>

<p>
UK 317:
</p>

<blockquote><p>
<code>basic_string</code> has both a constructor and an assignment operator that
accepts an initializer list, <code>basic_regex</code> should have the same.
</p></blockquote>

<p>
JP 74:
</p>

<blockquote><p>
<code>basic_regex &amp; operator= (initializer_list&lt;T&gt;);</code> is not defined.
</p></blockquote>

<p><i>[
Batavia (2009-05):
]</i></p>

<blockquote><p>
UK 317 asks for both assignment and constructor,
but the requested constructor is already present in the current Working Paper.
We agree with the proposed resolution.
Move to Tentatively Ready.
</p></blockquote>


<p id="res-1014"><b>Proposed resolution:</b></p>
<p>
Change 28.6.7 <a href="https://wg21.link/re.regex">[re.regex]</a>:
</p>

<blockquote><pre>
template &lt;class charT,
          class traits = regex_traits&lt;charT&gt; &gt;
class basic_regex {
  ...
  basic_regex&amp; operator=(const charT* ptr);
  <ins>basic_regex&amp; operator=(initializer_list&lt;charT&gt; il);</ins>
  template &lt;class ST, class SA&gt;
    basic_regex&amp; operator=(const basic_string&lt;charT, ST, SA&gt;&amp; p);
  ...
};
</pre></blockquote>

<p>
Add in  28.6.7.2 <a href="https://wg21.link/re.regex.construct">[re.regex.construct]</a>:
</p>

<blockquote>
<blockquote><p>
-20- ...
</p></blockquote>
<pre>
basic_regex&amp; operator=(initializer_list&lt;charT&gt; il);
</pre>
<blockquote><p>
-21- <i>Effects:</i> returns <code>assign(il.begin(), il.end());</code>
</p></blockquote>
</blockquote>






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