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Explicit and partial template specialization nested in classes.

Dear all,

the following code is illegeal (but compiles with MSVC 7.1):

// *** illegal ***
struct outer0 {
template<typena me inner_var>
struct inner { };

template<>
struct inner<void> { };
};
// ***

but is the following legal (compiles with g++, comeau, MSVC7.1) ?

// *** legal ***
struct outer0 {
template<typena me inner_var, typename hack = void>
struct inner { };

template<typena me hack>
struct inner<void,hack > { };
};
// ***

Example copied from:
http://lists.debian.org/debian-gcc/2.../msg00015.html

There I found as well:
In an explicit specialization declaration for a member of a class
template or a member template that appears in namespace scope, the
member template and some of its enclosing class templates may remain
unspecialized, except that the declaration shall not explicitly
specialize a class member template if its enclosing class templates
are not explicitly specialized as well.


but it does not tell if its legal :(.

Regards,
Patrick
Jul 22 '05 #1
0 1505

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