[boost] Re: Library TR draft available

From: David Abrahams (dave_at_[hidden])
Date: 2004-11-11 09:24:24

Beman Dawes <bdawes_at_[hidden]> writes:

> At 11:24 AM 11/10/2004, David Abrahams wrote:
>  >Beman Dawes <bdawes_at_[hidden]> writes:
>  >
>  >> The latest draft of the C++ Standard Library Technical Report is now
>  >> available at
>  >> http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2004/n1711.pdf
>  >>
>  >> There may be editorial (non-substantiative) changes to the final
>  >> version of the TR document, but this latest draft is believed to be
>  >> final in terms of technical content. Thus it should be safe for
>  >> implementors or users to write code based on this latest draft.
>  >>
>  >> It will be several years before most compilers come with a full
>  >> implementation of the TR. But some vendors (Metrowerks, for example)
>  >> are already shipping a few TR components. That brings up the question
>  >> of what Boost code does during the transition.
>  >>
>  >> To insure Boost code works with various TR implementations, some Boost
>  >> code will want to use the compiler vendor's version of the TR if the
>  >> TR component required is available, but otherwise will want to use
>  >> Boost equivalent code. How do we handle that?  The TR doesn't provide
>  >> in configuration macros, so I guess we will have to roll our own.
>  >
>  >Provide a switch that allows Boost headers to #include the appropriate
>  >TR components and re-publish them with using declarations?
>  >
>  >It's not perfect; there will be some differences in ADL behavior
>  >because those types are actually in different namespaces.
>
> That sounds like a possibility.
>
> I was thinking of an approach that used a namespace alias. If a
> vendor's version of the TR was to be used, the alias would be to
> std::tr1, otherwise it would be to the appropriate boost
> sub-namespace. Which particular alias was used would be controlled by
> #ifdef's.

I don't think it will work for boost::shared_ptr unless we're going
to move it to a sub-namespace.

-- 
Dave Abrahams
Boost Consulting
http://www.boost-consulting.com