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From: holly@python.cis.ohio-state.edu (Joe Hollingsworth)
Newsgroups: comp.lang.ada
Subject: Re: layering with discriminants
Message-ID: <90348@tut.cis.ohio-state.edu>
Date: 4 Mar 91 02:52:59 GMT
References: <44963@ut-emx.uucp>
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Reply-To: Joe Hollingsworth <holly@cis.ohio-state.edu>
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In article <44963@ut-emx.uucp> hasan@emx.utexas.edu (David A. Hasan) writes:
...stuff deleted...
>My problem revolves around the fact that the DEC compiler rejects
>the presence of the discriminant in the full declaration of the adt in
>the private part of g_highLevel, since the declaration is not a record.
>But the declaration is *derived* from a record.

>My conclusion is that it is not legal to derive
>types with discriminants from parents with discriminants.  
>If this is true, is there anyway to achieve an equivalent effect?

There's always this nagging problem when the compiler "rejects"
some program that you feed it:

Is the compiler right and this is not legal Ada, or is there a problem
with the compiler?

This question seems to come up frequently when trying things such
as what was described above.  (As for the above, I don't have an
answer.)

Makes one wonder if having two compilers (from different vendors)
"might" help answer the above question.  Probably not.

Joe
holly@cis.ohio-state.edu