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    CWG Issue 1131</TITLE>
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<P><EM>This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21
  Core Issues List revision 118b.
  See http://www.open-std.org/jtc1/sc22/wg21/ for the official
  list.</EM></P>
<P>2025-09-28</P>
<HR>
<A NAME="1131"></A><H4>1131.
  
Template aliases in <I>elaborated-type-specifier</I>s
</H4>
<B>Section: </B>9.2.9.5&#160; [<A href="https://wg21.link/dcl.type.elab">dcl.type.elab</A>]
 &#160;&#160;&#160;

 <B>Status: </B>C++11
 &#160;&#160;&#160;

 <B>Submitter: </B>US
 &#160;&#160;&#160;

 <B>Date: </B>2010-08-02<BR><BR>


<P>[Voted into the WP at the November, 2010 meeting.]</P>

<A href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2011/n3296.html#US41">N3092 comment
  US&#160;41<BR></A>

<P>The current wording disallows use of <I>typedef-name</I>s in
<I>elaborated-type-specifier</I>s. This prohibition should also
apply to template aliases:</P>

<PRE>
    struct A { };
    template&lt;typename T&gt; using X = A;
    struct X&lt;int&gt;* p2; // ill-formed
</PRE>

<P><B>Proposed resolution (August, 2010):</B></P>

<P>Change 9.2.9.5 [<A href="https://wg21.link/dcl.type.elab#2">dcl.type.elab</A>] paragraph 2 as follows:</P>

<BLOCKQUOTE>

...If the <I>identifier</I> resolves to a
<I>typedef-name</I> <INS>or the <I>simple-template-id</I>
resolves to an alias template specialization</INS>, the
<I>elaborated-type-specifier</I>  is ill-formed. [<I>Note:</I>...

</BLOCKQUOTE>

<P><I>[Note: this wording assumes the change from &#8220;template
alias&#8221; to &#8220;alias template&#8221; requested by comment
FI 11 on FCD N3092.]</I></P>

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