🚀 go-pugleaf

Robert DiFalco <difalco@primenet.com> writes:

>How do I define a nested class in a template?

You can define it either inline in the outer class declaration, or you
can just declare it in the outer class declaration and define it
later.  The latter method was allowed only relatively recently, and so
not all compilers support it yet.

>It seems to me that logic could offer this:
>
>   template <class Item>
>   class List_
>   {
>      public:
>         .
>         .
>         .
>         class Iterator;
>   };
>
>
>   template <class Item>
>   class List_<Item>::Iterator : public CollectionIterators_<Item>
>   {
>      .
>      .
>      .
>   };

Yep, that is exactly right.

>However, in Visual C++ 4.0, this produces the painfully ambiguous error
>message "error C2988: unrecognizable template declaration/definition".
>
>So, what gives? Is this an MSVC 4.0 problem, or am I use the incorrect
>syntax for defining a nested class outside of the outer classes scope?

It is an MSCV 4.0 problem.

As a work-around, try the following structure instead.

   template <class Item>
   class List_
   {
      public:
         .
         .
         .
         class Iterator {
		.
		.
		.
	};
   };

--
Fergus Henderson             	WWW: http://www.cs.mu.oz.au/~fjh
fjh@cs.mu.oz.au              	PGP: finger fjh@128.250.37.3
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