Re: [boost] [typeof] typeof emulation support for Borland

From: Peder Holt (peder.holt_at_[hidden])
Date: 2007-10-05 10:33:43

Workaround found.

Peder

2007/10/5, Peder Holt <peder.holt_at_[hidden]>:
> I am adding typeof emulation support for Borland, but have some
> trouble of adding template template support for Borland 5.9.2. (This
> problem was not present in Borland 5.8.2)
> The problem can be reduced to the following:
> template<class T, class U>
> struct t0;
>
> template<class T, int n>
> struct t1;
>
> template<template<class, class> class T, template<class, int> class U>
> struct t2;
>
>     struct non_template_works_ok {
>         template< class T0 , class T1 > struct decode_params;
>         template< template <class, class > class T0 , template <class,
> int  > class T1 >
>         struct decode_params< T0< int , int > , T1< int , (int )0 > > {
>             typedef t2<T0, T1> type;
>         };
>     };
>
>     template<std::size_t value>
>     struct template_specialization_worked_in_borland_5_8_2;
>     template<>
>     struct template_specialization_worked_in_borland_5_8_2<1>
>     {
>         template< class T0 , class T1 > struct decode_params;
>         template< template <class, class > class T0 , template <class,
> int  > class T1 >
>         struct decode_params< T0< int , int > , T1< int , (int )0 > > {
>             typedef t2<T0, T1> type;
>         };
>     };
>     template<typename T0,typename T1>
>     struct tester {
>         typedef typename
> non_template_works_ok::decode_params<T0,T1>::type type_ok;
>         typedef typename
> template_specialization_worked_in_borland_5_8_2<1>::decode_params<T0,T1>::type
> type_fails;
>     };
>     tester<t0<int,int>,t1<int,0> > a;
>
> Is there a workaround for this? In order to use the non-template
> version, each BOOST_TYPEOF_REGISTER_TEMPLATE would have to come up
> with a unique class name to be used for the decoding purpose.
>
> Regards
> Peder
>