On Jun 26, 1999, "Jeff Greif" <jmg@spam-me-not.trivida.com> wrote:

> Is it legal according to the standard?

Nope, it's explicitly forbidden in [temp.arg.nontype]/5, subitem 2.

> Is there some other way to express it?

I don't think so.

> Various kinds of casts in the typedef Ht<T,p> ht; line were
> attemped, but none could be parsed by the compiler

A template argument can't be the result of a type cast not involving
integral types.

--
Alexandre Oliva http://www.dcc.unicamp.br/~oliva IC-Unicamp, Bra[sz]il
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One compiler accepts this, but another does not, complaining about being
unable to convert d1 to a BaseFun<T>* in compiling class M.  Is it legal
according to the standard?  Is there some other way to express it?  Various
kinds of casts in the typedef Ht<T,p> ht; line were attemped, but none could
be parsed by the compiler which rejected the code as it is below.

-----------------------------------------------------------------------
template <class X> class BaseFun {};

template <class X> class DerivedFun1 : public BaseFun<X> {};

template <class T, BaseFun<T> *p> class Ht {};

template <class T, DerivedFun1<T> *p> class Hm {
private:
  typedef Ht<T,p> ht;
  ht rep;
public:
  Hm() {}
};


DerivedFun1<int> d1;

class M : public Hm<int, &d1> {};
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