Re: [boost] Boost.Preprocessor: Alternatives to defined(x)

From: David Abrahams (dave_at_[hidden])
Date: 2003-01-05 11:55:18

"Vesa Karvonen" <vesa_karvonen_at_[hidden]> writes:

> I'd like to propose adding suitable predicate macros, in particular
> BOOST_PP_IS_EMPTY(X), BOOST_PP_IS_1(X), BOOST_PP_IS_EMPTY_OR_1(X),

I like them (and I like the implementations)!

> to the Boost Preprocessor library to help detect whether flag like
> macros are defined. These macros would make it easier to move some
> logic from unusable #if blocks into usable macros.

Can you show an example of such a transformation?

-- 
                       David Abrahams
   dave_at_[hidden] * http://www.boost-consulting.com
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