🚀 go-pugleaf

In article <MATT.95Sep23125440@Austern>
martelli@cadlab.cadlab.it (Alex Martelli) writes:

> avoiding the template author the chore of thinking up a dummy type
> name in this situation...?  Or am I missing something here...?

You're missing something.

	template<class T> class X {
		int a;
		void f() {
			T::Pointer (a);		// *
		}
	};

If T::Pointer is the name of a type, the line with the comment
declares a local variable inside function f that is of type T::Pointer.
If, on the other hand, T::Pointer is the name of a function, then
the line with the comment calls that function passing it the
member names `a' of class X.

This shows that in general it is necessary for the compiler to know
whether each identifier is the name of a type.  In the case of members
of template parameters, there's no easy way to know that in advance,
so the "typename" keyword provides a way to say.
-- 
				--Andrew Koenig
				  ark@research.att.com
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