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From: Samuel Tardieu <sam@inf.enst.fr>
Subject: Re: Uninitialized "out" parameters
Date: 1996/07/19
Message-ID: <qw6pw5s1t82.fsf@gargantua.enst.fr>#1/1
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sender: tardieu@gargantua.enst.fr
references: <31EEACDA.64880EEB@sage.inel.gov> <4smh9i$gp5@krusty.irvine.com>
to: ica2ph@alpha1.csv.ica.uni-stuttgart.de (Peter Hermann),
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newsgroups: comp.lang.ada
Date: 1996-07-19T00:00:00+00:00
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Pascal> In Ada you can read out parameter, and this program is then
Pascal> not valid. It's behavior is unknown.

Peter> even more frightening Tuck?

I don't see what's frightening here. As I understand it, this point
has been introduced to allow things like this:

  procedure Fact (N : in Positive; R : out Positive) is
  begin
     R := 1;
     for I in 2 .. N loop
        R := R * I;       --  Note that the R out parameter gets read here
     end loop;
  end Fact;

If you forget to initialize R, then it's your fault and the compiler
may warn you as it may do for other uninitialized variables...

  Sam
-- 
"La cervelle des petits enfants, ca doit avoir comme un petit gout de noisette"
                                                       Charles Baudelaire