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    CWG Issue 1945</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="1945"></A><H4>1945.
  
Friend declarations naming members of class templates in non-templates
</H4>
<B>Section: </B>13.7.5&#160; [<A href="https://wg21.link/temp.friend">temp.friend</A>]
 &#160;&#160;&#160;

 <B>Status: </B>CD5
 &#160;&#160;&#160;

 <B>Submitter: </B>Richard Smith
 &#160;&#160;&#160;

 <B>Date: </B>2014-06-19<BR>


<P>During the discussion of <A HREF="1918.html">issue 1918</A>, it
was decided that the last part of the issue should be split off into a
separate issue.  According to 13.7.5 [<A href="https://wg21.link/temp.friend#5">temp.friend</A>] paragraph 5,</P>

<BLOCKQUOTE>

A member of a class template may be declared to be a friend of a
non-template class.

</BLOCKQUOTE>

<P>Does this make the example from <A HREF="1918.html">issue 1918</A>,</P>

<PRE>
  template&lt;typename T&gt; struct A {
    class B {
      class C {};
    };
  };
  class X {
    static int x;
    template &lt;typename T&gt; friend class A&lt;T&gt;::B::C;
  };
  template&lt;&gt; struct A&lt;int&gt; {
    typedef struct Q B;
  };
  struct Q {
    class C {
      int f() { return X::x; }
    };
  };
</PRE>

<P>ill-formed because the friend declaration does not refer to a
member of a class template?  This does not appear to be the
interpretation chosen by most implementations.</P>

<P><B>Additional note (January, 2024)</B></P>

<P>The example is ill-formed per the resolution of
<A HREF="1862.html">issue 1862</A> (adopted in November, 2017).</P>

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