Re: [boost] Request: new config macro

From: John Maddock (john_maddock_at_[hidden])
Date: 2002-08-03 05:35:39

> it seems that MSVC has problems with multiple default template
> arguments for class templates. For instance it doesn't understand the
> declaration in dynamic_bitset_fwd.hpp unless you re-write it in the
> (non-equivalent, of course) form:
>
>
> template <typename Block, typename Allocator = std::allocator<Block> >
> class dynamic_bitset;
>
>
> What about adding a new config macro, e.g.
> BOOST_NO_MULTIPLE_DEFAULT_TEMPLATE_ARGUMENTS, that deals with this?
>
>
> A test case for MSVC 6.0 SP5 is
>
>  template <class A = int, class B = A>
>   class Test {};
>
> which results in an internal compiler error.
>
>
> I'm not sure about the situations in which the problem reveals itself,
> so maybe the name of the macro isn't even appropriate but, regardless
> of the name, I think some macro is useful. Opinions?

Looks reasonable, I'll try and add it some time over the next few days
unless there are any other comments.

John Maddock
http://ourworld.compuserve.com/homepages/john_maddock/index.htm