Re: [boost] Re: [OT] Hiding template parameters [was: FC++ Formal review is...]

From: Gabriel Dos Reis (gdr_at_[hidden])
Date: 2004-02-16 12:46:26

David Abrahams <dave_at_[hidden]> writes:

| Gabriel Dos Reis <gdr_at_[hidden]> writes:
| 
| > Gennaro Prota <gennaro_prota_at_[hidden]> writes:
| >
| > | Just that with one rule the user can choose what the name should
| > | refer to, with the other one he/she cannot.
| >
| > I understand the reasoning of letting the user says what the name
| > should refer to.  Which makes me inclined to make the construct
| > ill-formed: That is not different from the rule that says you cannot 
| > reclare a template-parameter in its scope.
| 
| That would be horrible for generic code.

Care to explain why?

|  What are the requirements
| on the T parameter of this class template?
| 
|    template <class T>
|    struct Der : T
|    {
|       template <class U>
|       void f(U x)
|       {}
|    };

Should those requirements be different from those for

     template<class S>
     struct Der : S
     {
        template<class U>
        void f(U x)
        { } 
     };

?

-- Gaby