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From: dlwester@hotmail.com (Don Westermeyer)
Newsgroups: comp.lang.ada
Subject: Re: Elaboration of nested generic package.
Date: 10 Jul 2003 08:03:14 -0700
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"Robert I. Eachus" <rieachus@attbi.com> wrote in message news:<3F0CC2D1.10904@attbi.com>...
> 
>>
> But in general, if the compiler can't figure it out, the programmer is 
> very unlikely to have a decent answer in mind.
>

Well, some compilers do better at this than others, and in the case of
one compiler I've worked it apparently just picks a fairly random
order in which to elaborate things.  The elaborate pragmas pretty much
guarantee elaboration dependancy problems are caught at compile/link
time vs. execution (where on target hardware the debugging can be
quite difficult - especially exceptions during elaboration).

Another problem is when using packages written by others you may not
know if it needs to be elaborated or not.  For instance by just simply
declaring a variable one can set off a complex series of program
statements.

Seems to me that it is always safer to use the pragmas.  As long as
circular dependancies are avoided the compile will have no difficulty
with this.


At least Ada provides decent error checking for elaboration issues. 
Other languages (like Borland Delphi for instance) will just let you
hang yourself if you get too fancy during elaboration.