Re: Child vs nested package : efficiency matter

["Yannick Duchêne (Hibou57)" <yannick_duchene@yahoo.fr>]

Le Tue, 01 Jun 2010 21:44:46 +0200, Adam Beneschan <adam@irvine.com> a  
écrit:
> It was just a theory.  My thinking was that if you have a global
> variable in a package *body* (and no subunits), a compiler can, in
> theory, draw some conclusions about how the variable is used, since
> there can be no uses of the variable except by subprograms in the
> package body, and perhaps perform some optimizations based on that.
> This doesn't work if the variable is in the spec (even in the private
> part), since the compiler won't know what child packages might be
> added later that have access to the variable.  Anyway, this was just a
> theory, not really based on any experience.
While this could be, theoretically, also possible to do global  
optimization (SmallEiffel and its successor SmartEiffel compiler did  
this), compiling a program as a whole.

I understand what you mean, it's obvious.

-- 
There is even better than a pragma Assert: a SPARK --# check.
--# check C and WhoKnowWhat and YouKnowWho;
--# assert Ada;
--  i.e. forget about previous premises which leads to conclusion
--  and start with new conclusion as premise.