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From: "amado.alves" <amado.alves@netcabo.pt>
Newsgroups: comp.lang.ada
Subject: RE: In-Out Parameters for functions
Date: Fri, 23 Jan 2004 15:59:51 -0000
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Date: 2004-01-23T15:59:51+00:00

"I don't follow, and I would like to, because I find [IN] OUT params
for functions very useful. Could you please elaborate on that a bit
more?"
Maybe the most common example is the idiom (illegal in Ada):
  while Next (Item) loop
    Do_Something (Item);
  end loop;
where the Next function returns false in no more items are available,
and Item is an (illegal) in out parameter which holds the result of
a 'successful' call (and holds garbage on unsuccessful calls--this is=20
the ugly bit). The above idiom is perhaps the most clean solution for
the associated problem. I know I invariably use it when I write in C.
(Sorry for the possibly illformatted text.=20
I'm stuck with a crapy webmail system.)