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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="465"><a href="lwg-defects.html#465">465</a>. Contents of &lt;ciso646></h3>
<p><b>Section:</b> 16.4.2.3 <a href="https://wg21.link/headers">[headers]</a> <b>Status:</b> <a href="lwg-active.html#CD1">CD1</a>
 <b>Submitter:</b> Steve Clamage <b>Opened:</b> 2004-06-03 <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#headers">issues</a> in [headers].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#CD1">CD1</a> status.</p>
<p><b>Discussion:</b></p>
<p>C header &lt;iso646.h> defines macros for some operators, such as
not_eq for !=.</p>

<p>Section 16.4.2.3 <a href="https://wg21.link/headers">[headers]</a> "Headers" says that except as noted in
clauses 18 through 27, the &lt;cname> C++ header contents are the same
as the C header &lt;name.h>. In particular, table 12 lists
&lt;ciso646> as a C++ header.</p>

<p>I don't find any other mention of &lt;ciso646>, or any mention of
&lt;iso646.h>, in clauses 17 thorough 27. That implies that the
contents of &lt;ciso646> are the same as C header &lt;iso646.h>.</p>

<p>Annex C (informative, not normative) in [diff.header.iso646.h] C.2.2.2
"Header &lt;iso646.h>" says that the alternative tokens are not
defined as macros in &lt;ciso646>, but does not mention the contents
of &lt;iso646.h>.</p>

<p>I don't find any normative text to support C.2.2.2.</p>



<p id="res-465"><b>Proposed resolution:</b></p>
<p>Add to section 17.4.1.2 Headers [lib.headers] a new paragraph after
  paragraph 6 (the one about functions must be functions):</p> 

<blockquote>
<p>Identifiers that are keywords or operators in C++ shall not be defined
as macros in C++ standard library headers. 
[Footnote:In particular, including the standard header &lt;iso646.h>
or &lt;ciso646> has no effect. </p>
</blockquote>

<p><i>[post-Redmond: Steve provided wording.]</i></p>







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