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From: "Andrei Alexandrescu" <alexandrescua@micromodeling.com>
Subject: Re: Protected Inheritance
Date: 1999/02/17
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Valentin Bonnard wrote in message <36C046BE.4233@clipper.ens.fr>...
>No, sadly it won't, because of some strange [moderators, I can say
>stupid ?]
>rule in the standard, which prohibits making template parameters
>friends.

Guess what. I removed the "class" keyword in my friend declaration and MSVC
6 gladly accepted the code.

template <class T>
class DontDeriveFromMyTemplateParameter
{
    friend T;
    DontDeriveFromMyTemplateParameter() {}
};

class Something : virtual public
DontDeriveFromMyTemplateParameter<Something>
{
public:
    Something() {}
};

class SomethingElse : public Something
{
};

Something s1;          // fine
SomethingElse s2;      // compile-time error

So, who's right?
Also, to Scott: I tried the copy constructor loophole and I couldn't
instantiate MoreDerived as you predicted. Again: who's right?

Andrei



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