Explicit specialization problem

Explicit specialization problem

[Yogesh Kini]

Hi,
	When I compile the below code using gcc 3.3 I get the errors as below.
But MS VC++ compiles it straight. Can any one please tell me what the problem is?

Thanks,
Yogesh

namespace xyz
{
	template<class A, class B, class C>	
	class ABC
	{
		template<bool T>
		struct M
		{
			float a,b,c;		
		};
		
		template<>
		struct M<true>  -> Error here
		{
			int i,j,k;
		};
	};
	
};



main.cpp:59: error: enclosing class templates are not explicitly specialized
main.cpp:61: error: template parameters not used in partial specialization:
main.cpp:61: error:         `A'
main.cpp:61: error:         `B'
main.cpp:61: error:         `C'


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Re: Explicit specialization problem

[Nathan Sidwell]

Yogesh Kini wrote:
> Hi,
> 	When I compile the below code using gcc 3.3 I get the errors as below.
> But MS VC++ compiles it straight. Can any one please tell me what the problem is?
> 
> Thanks,
> Yogesh
> 
> namespace xyz
> {
> 	template<class A, class B, class C>	
> 	class ABC
> 	{
> 		template<bool T>
> 		struct M
> 		{
> 			float a,b,c;		
> 		};
> 		
> 		template<>
> 		struct M<true>  -> Error here
> 		{
> 			int i,j,k;
> 		};
> 	};
> 	
> };
This is ill-formed. For two reasons

1) [14.7.3]/2 says an explicit specialization of a member template shall
be declared in the namespace of the enclosing class.  I.e. you
have to move the M<true> specialization out.

2) [14.7.3]/18 says that an explicit specialization of a member class template
of a templated class must also specialize the outer class. I.e. you
cannot put a specialized class inside a non-specialized class.

nathan
-- 
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