[boost] Re: Bug: mpl::is_sequence (on MSVC7, at least)

From: David Abrahams (dave_at_[hidden])
Date: 2003-06-09 06:41:30

"Eric Friedman" <ebf_at_[hidden]> writes:

> I've found that mpl::is_sequence fails to operate correctly on certain types
> under MSVC7. I haven't tested extensively, but there certainly seems to be
> some problem with class templates from namespace std. (The problem likely
> extends to other types in other namespaces, and perhaps other compilers, but
> I have not investigated the issue thoroughly enough.)

Just msvc6.  The problem is that the workarounds used for vc are
somewhat limited.  One solution I can see is to change the "or_"
below into an "and_" and update mpl::list to use a "_tag" as well.
Making that change touches lots of files, though, so I'll let Aleksey
do it.

    template< typename T > struct is_sequence_impl
        : or_<
              identity< aux::has_tag<T> >
            , identity< aux::has_begin<T> >
            >
    {
    };

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com