Topic: Why no constraint templates ?
Author: croizier@rennes.enst-bretagne.fr (Valery Croizier)
Date: 1995/10/05 Raw View
Sometimes, I wish I could oblige the user of a template class to
inherit from a given class:
class Shape {
public:
void draw() = 0;
};
template <class T inherits from Shape>
class ListOfShape {
public:
// ...
void drawAll();
};
Of course, the above is just an example, and we can find many other
use of such a kind of template. The main advantage is compile-time
type-checking: when you write the implementation of the template class,
you cannot call a bad method.
o Is there a way I have not noticed to do this ?
o Does anybody know the reason why the team working on the
standard rejected this feature ?
--
Valery
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