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<title>Issue 238: Contradictory results of stringbuf initialization.</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#CD1">CD1</a> status.</em></p>
<h3 id="238"><a href="lwg-defects.html#238">238</a>. Contradictory results of stringbuf initialization.</h3>
<p><b>Section:</b> 31.8.2.2 <a href="https://wg21.link/stringbuf.cons">[stringbuf.cons]</a> <b>Status:</b> <a href="lwg-active.html#CD1">CD1</a>
 <b>Submitter:</b> Dietmar K&uuml;hl <b>Opened:</b> 2000-05-11 <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#stringbuf.cons">issues</a> in [stringbuf.cons].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#CD1">CD1</a> status.</p>
<p><b>Discussion:</b></p>
<p>In 27.7.1.1 paragraph 4 the results of calling the constructor of
'basic_stringbuf' are said to be <code>str() == str</code>. This is fine
that far but consider this code:</p>

<pre>
  std::basic_stringbuf&lt;char&gt; sbuf("hello, world", std::ios_base::openmode(0));
  std::cout &lt;&lt; "'" &lt;&lt; sbuf.str() &lt;&lt; "'\n";
</pre>

<p>Paragraph 3 of 27.7.1.1 basically says that in this case neither
the output sequence nor the input sequence is initialized and
paragraph 2 of 27.7.1.2 basically says that <code>str()</code> either
returns the input or the output sequence. None of them is initialized,
ie. both are empty, in which case the return from <code>str()</code> is
defined to be <code>basic_string&lt;cT&gt;()</code>.</p>

<p>However, probably only test cases in some testsuites will detect this
"problem"...</p>


<p id="res-238"><b>Proposed resolution:</b></p>
<p>Remove 27.7.1.1 paragraph 4.</p>


<p><b>Rationale:</b></p>
<p>We could fix 27.7.1.1 paragraph 4, but there would be no point.  If
we fixed it, it would say just the same thing as text that's already
in the standard.</p>




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