Den 08-05-2011 18:37, Joaquin M Lopez Munoz skrev:
You can decompose a pointer to member *type* into its constituents easily enough (even in C++98), but when you write
ordered_unique<&foo::x>
the entity passed to ordered_unique is not a *type* but a pointer (to a member). That's why you need decltype to do the object-->type magic, and that's why the syntax you propose can't work.
Apologizes for my ignorance. The following compiles fine for me: class Bar { public: int var; }; template< class T, class U> void foo( T U::* ptr ) { } but I see your point. What a pitty the language is a barior here. We simply can't create a class template without adding two arguments for the ruturn type and the class type. Thanks for explaining. Your solution is still pretty nice. -Thorsten