This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21 Core Issues List revision 115d. See http://www.open-std.org/jtc1/sc22/wg21/ for the official list.
2024-10-26
[Voted into the WP at the November, 2010 meeting.]
N3092 comment US 74An alias-declaration allows a class or enumeration type to be defined in its type-id (9.2.9 [dcl.type] paragraph 3). However, it's not clear that this is desirable when the alias-declaration is part of a template alias:
template<typename T> using A = struct { void f(T) { } };
Proposed resolution (August, 2010):
Change 9.2.9 [dcl.type] paragraph 3 as follows:
...A type-specifier-seq shall not define a class or enumeration unless it appears in the type-id of an alias-declaration (9.2.4 [dcl.typedef]) that is not the declaration of a template-declaration.