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<title>Issue 655: Signature of generate_canonical not useful</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="655"><a href="lwg-defects.html#655">655</a>. Signature of generate_canonical not useful</h3>
<p><b>Section:</b> 29.5.8.2 <a href="https://wg21.link/rand.util.canonical">[rand.util.canonical]</a> <b>Status:</b> <a href="lwg-active.html#CD1">CD1</a>
 <b>Submitter:</b> Daniel Kr&uuml;gler <b>Opened:</b> 2007-03-08 <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.util.canonical">issues</a> in [rand.util.canonical].</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 29.5.2 <a href="https://wg21.link/rand.synopsis">[rand.synopsis]</a> we have the declaration
</p>

<blockquote><pre>
template&lt;class RealType, class UniformRandomNumberGenerator,
  size_t bits&gt;
result_type generate_canonical(UniformRandomNumberGenerator&amp; g);
</pre></blockquote>

<p>
Besides the "result_type" issue (already recognized by Bo Persson
at Sun, 11 Feb 2007 05:26:47 GMT in this group) it's clear, that
the template parameter order is not reasonably choosen: Obviously
one always needs to specify all three parameters, although usually
only two are required, namely the result type RealType and the
wanted bits, because UniformRandomNumberGenerator can usually
be deduced.
</p>

<p>
See <a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2391.pdf">N2391</a> and
<a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2423.pdf">N2423</a>
for some further discussion.
</p>


<p id="res-655"><b>Proposed resolution:</b></p>
<p>
Adopt the proposed resolution in
<a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2423.pdf">N2423</a>.
</p>


<p><i>[
Kona (2007): The LWG adopted the proposed resolution of N2423 for this issue.
The LWG voted to accelerate this issue to Ready status to be voted into the WP at Kona.
]</i></p>





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