Re: Recursive template question
lutorm wrote:
I have a class which is templated by a policy which needs to know the
type of the class it's "policying". Ie, I want to do something like:
template <class C> class policy {
C* fun(); // it needs to know the type of C here
};
template <class policy> class useful : public
policy<useful<policy<useful... TROUBLE!
I suppose I could do it by doing
template <template <class> class C, class Ctemparg> class policy {
C<Ctemparg>* fun();
};
template <class policy> class useful : public policy<useful,policy> {};
Is there any way out of this dilemma?
If I understand the problem correctly, I would recommend declaring a
policy class template first and then declare a specialization of that
policy class template. The program would then use the specialization:
// policy general template
template <class T>
struct policy; // not defined
// specialization for program use
template < template <class> class U, class T>
struct policy<U<T> >
{
};
// user general template
template <class T>
struct user : policy< user<T> >
{
};
Greg
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