From: David Abrahams (david.abrahams_at_[hidden])
Date: 2001-09-29 08:24:51
----- Original Message -----
From: "Eric Ford" <eford_at_[hidden]>
> I haven't been paying attention to the discussions about a boost build
> system for libraries requiring code not in header files. In principle
> that could generate a header file with constants such as these that
> were necessary for some functions. The only alternative I can see is
> a lot of ugly #ifdef's or code that will only compile with a deplate
> depth of significantly greater than 17. Using a build system to
> generate headers would be somewhat inelegant. On the plus side, it
> would introduce the least possible overhead, since the constants would
> just be constants (after the first compile) and not need to be
> calculated either at run time or at compile time. However, I'm not
> sure if this would be acceptable to the rest of the boost crew. I
> could understand some being very opposed to relying on machine
> generated header files.
There is already precedent for it. Various libraries, including the Python
and PREPROCESSOR libraries, include generated headers.
> Comments from the boost powers that be? Is this functionality that
> the boost build system could provide?
Sure, if somebody writes the generator program. Boost.Build already works
with lex and yacc / flex and bison.
> How far in the future before
> such a build system is functional? Ready to be included in the boost
Well, it's already functional and AFAIK in the distribution, but there are
lots of things still on the TODO list. My work on the build system is going
to be a bit slow in the immediate future while I seek employment.
David Abrahams, C++ library designer for hire
C++ Booster (http://www.boost.org)
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