Re: Conditional compilation in Ada?

[Marin David Condic <nobody@noplace.com>]

Unfortunately, there isn't any standard Ada way of dealing with 
conditional compilation and not a whole lot of sympathy for it with most 
people in the Ada crowd. (Probably because they've seen it abused so 
much in C programs that they'd rather not allow it into the language 
lest it cause Ada programs to turn into the sort of unholy mess many C 
programs have become.)

People have mentioned gnatprep as a possible answer - which is fine so 
long as all you ever want to use is gnat. If you were dealing with code 
that needed to be made portable across two or more Ada compilers, you'd 
have a problem because gnatprep isn't standard across all compilers. 
(You could probably cobble something together though since it is open 
source.) You can also try pulling some information-hiding tricks and 
isolation of stuff down to package bodies & utilize some form of 
configuration management outside the bounds of Ada to get the desired 
effect. However that often seems to me to be a) overly complicated for 
occasional small problems and b) another non-standard way of dealing 
with the problem.

If you really have large platform/compiler dependent issues, you're 
probably better off biting the bullet and using some kind of 
configuration management tools with isolation of whatever is dependent 
within package bodies. For the smaller-scale problems, you're stuck with 
  only sub-optimal answers.

MDC

jtg wrote:
> I am using Ada for many years now, but recently
> I stumbled upon a problem I cannot solve: I need
> some kind of conditional preprocessing, which is
> commonly used in C programs:

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