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<title>Issue 1192: basic_string missing definitions for cbegin &#47; cend &#47; crbegin &#47; crend</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="1192"><a href="lwg-defects.html#1192">1192</a>. <code>basic_string</code> missing definitions for <code>cbegin</code> &#47; <code>cend</code> &#47; <code>crbegin</code> &#47; <code>crend</code></h3>
<p><b>Section:</b> 27.4.3.4 <a href="https://wg21.link/string.iterators">[string.iterators]</a> <b>Status:</b> <a href="lwg-active.html#C++11">C++11</a>
 <b>Submitter:</b> Jonathan Wakely <b>Opened:</b> 2009-08-14 <b>Last modified:</b> 2016-01-28</p>
<p><b>Priority: </b>Not Prioritized
</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>
Unlike the containers in clause 23, <code>basic_string</code> has definitions for
<code>begin()</code> and <code>end()</code>, but these have not been updated to include <code>cbegin</code>,
<code>cend</code>, <code>crbegin</code> and <code>crend</code>.
</p>

<p><i>[
2009-10-28 Howard:
]</i></p>


<blockquote><p>
Moved to Tentatively NAD after 5 positive votes on c++std-lib.  Added
rationale.
</p></blockquote>

<p><i>[
2009-10-28 Alisdair disagrees:
]</i></p>


<blockquote>
<p>
I'm going to have to speak up as the dissenting voice.
</p>

<p>
I agree the issue could be handled editorially, and that would be my
preference if Pete feels this is appropriate. Failing that, I really
think this issue should be accepted and moved to ready.  The other
begin&#47;end functions all have a semantic definition for this template,
and it is confusing if a small few are missing.
</p>

<p>
I agree that an alternative would be to strike <em>all</em> the definitions for
<code>begin&#47;end&#47;rbegin&#47;rend</code> and defer completely to the requirements tables in
clause 23.  I think that might be confusing without a forward reference
though, as those tables are defined in a <em>later</em> clause than the
<code>basic_string</code> template itself.  If someone wants to pursue this I would
support it, but recommend it as a separate issue.
</p>

<p>
So my preference is strongly to move Ready over NAD, and a stronger
preference for NAD Editorial if Pete is happy to make these changes.
</p>

</blockquote>

<p><i>[
2009-10-29 Howard:
]</i></p>


<blockquote><p>
Moved to Tentatively Ready after 5 positive votes on c++std-lib.  Removed
rationale to mark it NAD.  :-)
</p></blockquote>



<p id="res-1192"><b>Proposed resolution:</b></p>
<p>
Add to 27.4.3.4 <a href="https://wg21.link/string.iterators">[string.iterators]</a>
</p>

<blockquote><pre>
iterator       begin();
const_iterator begin() const;
<ins>const_iterator cbegin() const;</ins>
</pre>

<p>...</p>

<pre>
iterator       end();
const_iterator end() const;
<ins>const_iterator cend() const;</ins>
</pre>

<p>...</p>

<pre>
reverse_iterator       rbegin();
const_reverse_iterator rbegin() const;
<ins>const_reverse_iterator crbegin() const;</ins>
</pre>

<p>...</p>

<pre>
reverse_iterator       rend();
const_reverse_iterator rend() const;
<ins>const_reverse_iterator crend() const;</ins>
</pre>

</blockquote>





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