🚀 go-pugleaf

Excerpts from netnews.comp.lang.c++: 6-Oct-92 Re: The concept of
template.. Andrew Koenig@alice.att. (1825)
> If we call f with an argument of type Bar, it will fail during instantiation
> with an ambiguity error.  The only way to avoid this is to say that the type
> constraint also constrains the call of t.mem(0) to just those instances of
> mem defined in the base class -- but in that case, you will still get in
> trouble with this one:

> 	class Baz: public Foo {
> 	public:
> 		void mem(long);
> 		void mem(double);
> 	};

> because now *neither* of the variants of Baz::mem matches the one in Foo.
> Thus, you have two choices:

> 	1. Attempt to call Baz::mem(int), which doesn't exist;

> 	2. Call Foo::mem(int), in which case you might as well not
> 	   bother using templates at all, or

> 	3. Give an ambiguity error, in which case you can't type-check
> 	   the original template.

> My point in giving this example is to show that statements like `constraining
> template types makes compile-time type checking possible' cannot be made
> casually -- it is the responsibility of the person making such a statement
> to provide evidence that the statement is indeed true.

> This stuff is **difficult**!  Don't take it lightly!
> -- 
> 				--Andrew Koenig
> 				  ark@europa.att.com

What's the problem ?

Why not take option 2 ?

Every Baz object has method Foo::mem(int) cause it has inherited it
from Foo.
If you don't agree with it, why use inheritance ?

And if you would like it to call anything else, then you programming 
style seems weird to me !!!

	Stefan

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