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From: Stephen Leake <Stephe.Leake@nasa.gov>
Newsgroups: comp.lang.ada
Subject: Re: How to Emulate C++ Macro with Static Local Variable?
Date: 25 Sep 2003 09:43:31 -0400
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Hyman Rosen <hyrosen@mail.com> writes:

> Robert I. Eachus wrote:
> > This code is a bit ugly, but it does compile.  And since Bar_Pointer
> > is a constant, you can't accidently pass it to Test.  There might be
> > a cleaner cleverer way to do it, but this works.
> > The cleanest option may be to run your code through a preprocessor
> > and use a similar macro.
> 
> Robert, I'm almost ashamed of you! You're abandoning your Ada ways
> and starting to think like a C++ hacker! :-)

AMEN!

> The whole design is wrong in the C++ to begin with. If you want to
> have a memoizing function, the job of caching old values belongs to
> the function itself, not scattered in macros and variables all over
> the place.

Yes, that is probably the best way. Although it may be that the state
should be preserved at a higher level; depends on the details.

> In Ada, I suppose that I would just stick bar(foo:integer) into a
> package, then have one of the Charles maps in the same package to
> hold memoized values. 

The C code did not dynamically allocate memo state, but that is
certainly a reasonable improvement.

-- 
-- Stephe