<HTML>
<HEAD>
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
<TITLE>
    CWG Issue 1182</TITLE>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<STYLE TYPE="text/css">
  INS { text-decoration:none; font-weight:bold; background-color:#A0FFA0 }
  .INS { text-decoration:none; background-color:#D0FFD0 }
  DEL { text-decoration:line-through; background-color:#FFA0A0 }
  .DEL { text-decoration:line-through; background-color: #FFD0D0 }
  @media (prefers-color-scheme: dark) {
    HTML { background-color:#202020; color:#f0f0f0; }
    A { color:#5bc0ff; }
    A:visited { color:#c6a8ff; }
    A:hover, a:focus { color:#afd7ff; }
    INS { background-color:#033a16; color:#aff5b4; }
    .INS { background-color: #033a16; }
    DEL { background-color:#67060c; color:#ffdcd7; }
    .DEL { background-color:#67060c; }
  }
  SPAN.cmnt { font-family:Times; font-style:italic }
</STYLE>
</HEAD>
<BODY>
<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="1182"></A><H4>1182.
  
Incorrect description of pack expansion syntax
</H4>
<B>Section: </B>13.7.4&#160; [<A href="https://wg21.link/temp.variadic">temp.variadic</A>]
 &#160;&#160;&#160;

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

 <B>Submitter: </B>Daveed Vandevoorde
 &#160;&#160;&#160;

 <B>Date: </B>2010-08-26<BR>


<P>[Voted into the WP at the March, 2011 meeting as part of paper N3270.]</P>

<P>According to 13.7.4 [<A href="https://wg21.link/temp.variadic#4">temp.variadic</A>] paragraph 4,</P>

<BLOCKQUOTE>

A <I>pack expansion</I> is a sequence of tokens that names one or more
parameter packs, followed by an ellipsis.

</BLOCKQUOTE>

<P>This is contradicted by 7.6.2.5 [<A href="https://wg21.link/expr.sizeof#5">expr.sizeof</A>] paragraph 5,
which describes <TT>sizeof...(Types)</TT> as an expansion, as well
as the case where the expansion appears in a declarator like the
example given in 9.3.4.6 [<A href="https://wg21.link/dcl.fct#13">dcl.fct</A>] paragraph 13:
</P>

<PRE>
    template&lt;typename... T&gt; void f(T (* ...t)(int, int));
</PRE>

<P>This is also described as a pack expansion, although it does
not fit the syntactic summary.</P>

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

<P>This issue is resolved by the resolution of
<A HREF="778.html">issue 778</A>.</P>

<BR><BR>
</BODY>
</HTML>
