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<title>Issue 332: Consider adding increment and decrement operators to std::fpos&lt; T &gt; </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#NAD">NAD</a> status.</em></p>
<h3 id="332"><a href="lwg-closed.html#332">332</a>. Consider adding increment and decrement operators to std::fpos&lt; T &gt; </h3>
<p><b>Section:</b> 31.5.3 <a href="https://wg21.link/fpos">[fpos]</a> <b>Status:</b> <a href="lwg-active.html#NAD">NAD</a>
 <b>Submitter:</b> PremAnand M. Rao <b>Opened:</b> 2001-08-27 <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#fpos">issues</a> in [fpos].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#NAD">NAD</a> status.</p>
<p><b>Discussion:</b></p>
<p>
Increment and decrement operators are missing from 
Table 88 -- Position type requirements in 31.5.3 <a href="https://wg21.link/fpos">[fpos]</a>.
</p>


<p id="res-332"><b>Proposed resolution:</b></p>
<p>
Table 88 (section 27.4.3) -- Position type requirements
be updated to include increment and decrement operators.
</p>

<pre>
expression        return type     operational    note

++p               fpos&amp;           p += O(1)
p++               fpos            { P tmp = p;
                                    ++p;
                                    return tmp; }
--p               fpos&amp;           p -= O(1)
p--               fpos            { P tmp = p;
                                    --p;
                                    return tmp; }
</pre>



<p><b>Rationale:</b></p>
<p>The LWG believes this is a request for extension, not a defect
report.  Additionally, nobody saw a clear need for this extension;
<code>fpos</code> is used only in very limited ways.</p>





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