🚀 go-pugleaf

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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