Re: [boost] [preprocessor] seq/size.hpp BOOST_PP_SEQ_SIZE MSVC empty list warning

Subject: Re: [boost] [preprocessor] seq/size.hpp BOOST_PP_SEQ_SIZE MSVC empty list warning
From: Jeffrey Lee Hellrung, Jr. (jeffrey.hellrung_at_[hidden])
Date: 2011-04-19 14:05:43

On Tue, Apr 19, 2011 at 8:29 AM, damien benoist <damien_benoist_at_[hidden]>wrote:

> Hello,
>
> It seems that BOOST_PP_SEQ_SIZE generates a warning
> with empty sequences under MSVC (vs 2010/boost 1.46.1).
>

There is no such a thing as a truly empty sequence:

http://www.boost.org/doc/libs/1_46_1/libs/preprocessor/doc/

Although you can kinda fake it through BOOST_PP_SEQ_NIL.

[...]

> More general question:
>
> I'm discovering boost.
> I'm really impressed by the macros in boost/preprocessor.
> It makes a lot of things possible.
>

Indeed.

> But it provides features the preprocessor was not
> meant for. For that, it uses a lot of tricks.
>

Indeed.  And a lot of workarounds for broken preprocessors.

How portable is it?
> How many architectures is it known to work/not work with?
>

I know the authors went to great lengths to make the library relatively
portable, but there *might* be some ancient compilers for which some parts
of the library are broken, I don't know.

> Can we be confident that it should work with any preprocessor?
>

Certainly for any standards-conforming preprocessor, and certainly not for
an arbitrarily-broken preprocessor :)

Thanks for your help.
>
[...]

- Jeff