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<title>Issue 810: Missing traits dependencies in operational semantics of extended manipulators</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="810"><a href="lwg-defects.html#810">810</a>. Missing traits dependencies in operational semantics of extended manipulators</h3>
<p><b>Section:</b> 31.7.8 <a href="https://wg21.link/ext.manip">[ext.manip]</a> <b>Status:</b> <a href="lwg-active.html#C++11">C++11</a>
 <b>Submitter:</b> Daniel Kr&uuml;gler <b>Opened:</b> 2008-03-01 <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#ext.manip">issues</a> in [ext.manip].</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>
The recent draft (as well as the original proposal n2072) uses an
operational semantic
for <code>get_money</code> ([ext.manip]/4) and <code>put_money</code> ([ext.manip]/6), which uses
</p>

<blockquote><pre>
istreambuf_iterator&lt;charT&gt;
</pre></blockquote>

<p>
and
</p>

<blockquote><pre>
ostreambuf_iterator&lt;charT&gt;
</pre></blockquote>

<p>
resp, instead of the iterator instances, with explicitly provided
traits argument (The operational semantic defined by <code>f</code> is also traits
dependent). This is an obvious oversight because both <code>*stream_buf</code>
c'tors expect a <code>basic_streambuf&lt;charT,traits&gt;</code> as argument.
</p>
<p>
The same problem occurs within the <code>get_time</code> and <code>put_time</code> semantic 
where additional to the problem we
have an editorial issue in <code>get_time</code> (<code>streambuf_iterator</code> instead of
<code>istreambuf_iterator</code>).
</p>

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

<blockquote>
<p>
This appears to be an issue of presentation.
</p>
<p>
We agree with the proposed resolution.
Move to Tentatively Ready.
</p>
</blockquote>


<p id="res-810"><b>Proposed resolution:</b></p>
<p>
In 31.7.8 <a href="https://wg21.link/ext.manip">[ext.manip]</a>/4 within function <code>f</code> replace the first line
</p>

<blockquote><pre>
template &lt;class charT, class traits, class moneyT&gt; 
void f(basic_ios&lt;charT, traits&gt;&amp; str, moneyT&amp; mon, bool intl) { 
   typedef istreambuf_iterator&lt;charT<ins>, traits</ins>&gt; Iter;
   ...
</pre></blockquote>

<p>
In 31.7.8 <a href="https://wg21.link/ext.manip">[ext.manip]</a>/5 remove the first template <code>charT</code> parameter:
</p>

<blockquote><pre>
template &lt;<del>class charT, </del>class moneyT&gt; unspecified put_money(const moneyT&amp; mon, bool intl = false<ins>)</ins>;
</pre></blockquote>

<p>
In 31.7.8 <a href="https://wg21.link/ext.manip">[ext.manip]</a>/6 within function <code>f</code> replace the first line
</p>

<blockquote><pre>
template &lt;class charT, class traits, class moneyT&gt; 
void f(basic_ios&lt;charT, traits&gt;&amp; str, const moneyT&amp; mon, bool intl) { 
  typedef ostreambuf_iterator&lt;charT<ins>, traits</ins>&gt; Iter;
  ...
</pre></blockquote>

<p>
In 31.7.8 <a href="https://wg21.link/ext.manip">[ext.manip]</a>/8 within function <code>f</code> replace the first line
</p>

<blockquote><pre>
template &lt;class charT, class traits&gt; 
void f(basic_ios&lt;charT, traits&gt;&amp; str, struct tm *tmb, const charT *fmt) { 
  typedef <ins>i</ins>streambuf_iterator&lt;charT<ins>, traits</ins>&gt; Iter;
  ...
</pre></blockquote>

<p>
In 31.7.8 <a href="https://wg21.link/ext.manip">[ext.manip]</a>/10 within function <code>f</code> replace the first line
</p>

<blockquote><pre>
template &lt;class charT, class traits&gt; 
void f(basic_ios&lt;charT, traits&gt;&amp; str, const struct tm *tmb, const charT *fmt) { 
  typedef ostreambuf_iterator&lt;charT<ins>, traits</ins>&gt; Iter;
  ...
</pre></blockquote>

<p>
In 31.7 <a href="https://wg21.link/iostream.format">[iostream.format]</a>, Header <code>&lt;iomanip&gt;</code> synopsis change:
</p>

<blockquote><pre>
template &lt;<del>class charT, </del>class moneyT&gt; T8 put_money(const moneyT&amp; mon, bool intl = false);
</pre></blockquote>





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