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<title>Issue 1179: Probably editorial in [structure.specifications]</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_Editorial">NAD Editorial</a> status.</em></p>
<h3 id="1179"><a href="lwg-closed.html#1179">1179</a>. Probably editorial in [structure.specifications]</h3>
<p><b>Section:</b> 16.3.2.4 <a href="https://wg21.link/structure.specifications">[structure.specifications]</a> <b>Status:</b> <a href="lwg-active.html#NAD_Editorial">NAD Editorial</a>
 <b>Submitter:</b> Robert Klarer <b>Opened:</b> 2009-07-21 <b>Last modified:</b> 2016-01-28</p>
<p><b>Priority: </b>Not Prioritized
</p>
<p><b>View other</b> <a href="lwg-index-open.html#structure.specifications">active issues</a> in [structure.specifications].</p>
<p><b>View all other</b> <a href="lwg-index.html#structure.specifications">issues</a> in [structure.specifications].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#NAD Editorial">NAD Editorial</a> status.</p>
<p><b>Discussion:</b></p>
<p>
While reviewing <a href="lwg-closed.html#971" title="Spurious diagnostic conversion function (Status: NAD)">971</a><sup><a href="https://cplusplus.github.io/LWG/issue971" title="Latest snapshot">(i)</a></sup> I noted that 16.3.2.4 <a href="https://wg21.link/structure.specifications">[structure.specifications]</a>/7 says:
</p>

<blockquote><p>
-7- Error conditions specify conditions where a function may fail. The
conditions are listed, together with a suitable explanation, as the <code>enum
class errc</code> constants (19.5) that could be used as an argument to
function <code>make_error_condition</code> (19.5.3.6).
</p></blockquote>

<p>
This paragraph should mention <code>make_error_code</code> or the text "that
could be used as an argument to function <code>make_error_condition</code>
(19.5.3.6)" should be deleted.  I believe this is editorial.
</p>

<p><i>[
2009-07-21 Chris adds:
]</i></p>


<blockquote>
<p>
I'm not convinced there's a problem there, because as far as the "Error
conditions" clauses are concerned, make_error_condition() is used by a
user to test for the condition, whereas make_error_code is not. For
example:
</p>

<blockquote><pre>
void foobar(error_code&amp; ec = throws());
</pre></blockquote>

<p>
 Error conditions:
</p>
<blockquote><p>
permission_denied - Insufficient privilege to perform operation.
</p></blockquote>

<p>
When a user writes:
</p>

<blockquote><pre>
error_code ec;
foobar(ec);
if (ec == errc::permission_denied)
   ...
</pre></blockquote>

<p>
the implicit conversion <code>errc-&gt;error_condition</code> makes the if-test
equivalent to:
</p>

<blockquote><pre>
if (ec == make_error_condition(errc::permission_denied))
</pre></blockquote>

<p>
On the other hand, if the user had written:
</p>

<blockquote><pre>
if (ec == make_error_code(errc::permission_denied))
</pre></blockquote>

<p>
the test is now checking for a specific error code. The test may
evaluate to <code>false</code> even though <code>foobar()</code> failed due to the documented
error condition "Insufficient privilege".
</p>
</blockquote>

<p><i>[
2009 Santa Cruz:
]</i></p>


<blockquote>
<p>
NAD Editorial.
</p>
<p>
What the WP says right now is literally true: these codes can be used as
an argument to <code>make_error_condition</code>. (It is also true that they can be
used as an argument to <code>make_error_code</code>, which the WP doesn't say.) Maybe
it would be clearer to just delete "that could be used as an argument to
function <code>make_error_condition</code>", since that fact is already implied by
other things that we say. We believe that this is editorial.
</p>
</blockquote>



<p id="res-1179"><b>Proposed resolution:</b></p>
<p>
</p>





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