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<title>Issue 505: Result_type in random distribution requirements</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="505"><a href="lwg-defects.html#505">505</a>. Result_type in random distribution requirements</h3>
<p><b>Section:</b> 29.5.3 <a href="https://wg21.link/rand.req">[rand.req]</a>, 99 [tr.rand.req] <b>Status:</b> <a href="lwg-active.html#CD1">CD1</a>
 <b>Submitter:</b> Walter Brown <b>Opened:</b> 2005-07-03 <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#rand.req">issues</a> in [rand.req].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#CD1">CD1</a> status.</p>
<p><b>Discussion:</b></p>
<p>
Table 17: Random distribution requirements
</p>
<p>
Row 1 requires that each random distribution provide a nested type "input_type";
this type denotes the type of the values that the distribution consumes.
</p>
<p>
Inspection of all distributions in [tr.rand.dist] reveals that each distribution
provides a second typedef ("result_type") that denotes the type of the values the
distribution produces when called.  
</p>


<p id="res-505"><b>Proposed resolution:</b></p>
<p>
It seems to me that this is also a requirement
for all distributions and should therefore be  indicated as such via a new second
row to this table 17:
</p>
<table border="1" cellpadding="5">
<tr><td>X::result_type</td><td>T</td><td>---</td><td>compile-time</td></tr>
</table>

<p><i>[
Berlin:  Voted to WP.  N1932 adopts the proposed resolution:  see Table 5 row 1.
]</i></p>







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