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    CWG Issue 335</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="335"></A><H4>335.
  
Allowing <TT>export</TT> on template members of nontemplate classes
</H4>
<B>Section: </B>Clause 13&#160; [<A href="https://wg21.link/temp">temp</A>]
 &#160;&#160;&#160;

 <B>Status: </B>CD1
 &#160;&#160;&#160;

 <B>Submitter: </B>John Spicer
 &#160;&#160;&#160;

 <B>Date: </B>30 Jan 2002<BR>


<P>[Voted into WP at April 2003 meeting.]</P>



<P>The syntax for "export" permits it only on template declarations.
Clause 13 [<A href="https://wg21.link/temp#6">temp</A>] paragraph 6 further restricts "export"
to appear only
on namespace scope declarations.  This means that you can't export
a member template of a non-template class, as in:
<PRE>
  class A {
    template &lt;class T&gt; void f(T);
  };
</PRE>
You can, of course, put export on the definition:
<PRE>
  export template &lt;class T&gt; void A&lt;T&gt;::f(T){}
</PRE>
but in order for the template to be used from other translation units
(the whole point of export) the declaration in the other translation
unit must also be declared export.</P>

<P>There is also the issue of whether or not we should permit this usage:
<PRE>
  export struct A {
    template &lt;class T&gt; void f(T);
  };
</PRE>
My initial reaction is to retain this prohibition as all current uses
of "export" are preceding the "template" keyword.</P>

<P>If we eliminate the requirement that "export" precede "template" there
is a similar issue regarding this case, which is currently prohibited:
<PRE>
  template &lt;class T&gt; struct B {
    export void f();
  };
</PRE>
My preference is still to permit only "export template".</P>

<P><B>Notes from the 4/02 meeting:</B></P>

<P>This is resolved by the proposed changes for
<A HREF="323.html">issue 323</A>.</P>

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