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From: Stephen Cleary <csclear@my-deja.com>
Subject: Re: [Q] Dependent template arguments
Date: 2000/06/28
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References: <B575744D-A430A@192.109.102.124>
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In article <B575744D-A430A@192.109.102.124>,
  "Gabor Greif" <gabor@no.netopia.com> wrote:
> I am evaluating what degree of dependency of template arguments is
> permitted by the standard...
>
> template <typename T, template <T> class F>
> struct foo {};
>
> Admittedly my example is rather contrived, but I did not find any
hint in
> the standard that this kind of dependency would be disallowed.

Since F is a template template argument, it needs a template parameter
list.  "<T>" is not a template parameter list.

You could do:
  template <typename T, template <T C> class F>
  struct foo {};
where F takes a non-type template argument of type T, or:
  template <typename T, template <typename> class _F>
  struct foo { typedef _F<T> F; };
where F takes a type template argument, which is T, or (if you *really*
want it in the template parameter list):
  template <typename T, template <typename> class _F,
      typename F = _F<T> >
  struct foo {};

        -Stephen Cleary


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