Re: Pragma for conditional compilation? (Ada 2005 vs. 95)

[Stephen Leake <stephen_leake@stephe-leake.org>]

Jean-Pierre Rosen <rosen@adalog.fr> writes:

> Ludovic Brenta a �crit :
>> Jean-Pierre Rosen writes:
>>> Library package renaming is a way to achieve the same effect without
>>> resorting to CM.
>> But what if you want to maintain two versions of the software in
>> parallel, like the OP does? You'll want two versions of the renaming.
>> I don't see how you'd do that without some sort of configuration
>> management system. OK, maybe I'm biased: I haven't worked without a
>> configuration management system since 1999 :)
>> 
> If you have something like:
>
> with OS_Services_Linux;
> package OS_Services renames OS_Services_Linux;
>
> You certainly need to edit the source to move to -say- a Windows
> version, but I claim that it is not much more work than changing the
> value of a variable in a Make file....

You can have _two_ make files, in two build directories, and compile
both without editing anything. Each top-level make file can define the
relevant variables, then call a common makefile that does the real
work.

Or you can have two GNAT project files that declare source names for
package OS_Services, again in two build directories, and compile both
without editing.

You can't do that with your solution.

You need two build directories anyway, since all (or at least some of)
the object files will be different.

A true solution involves _zero_ manual steps.

-- 
-- Stephe