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From: tmoran@bix.com
Subject: Re: 'Read for pointers
Date: 2000/07/26
Message-ID: <YEJf5.49$LV1.69164@news.pacbell.net>#1/1
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References: <lZIf5.190$wE4.35361@nnrp3.sbc.net>
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 26 Jul 2000 15:31:20 PDT)
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Newsgroups: comp.lang.ada
Date: 2000-07-26T00:00:00+00:00
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>Further to my previous post, to the effect that one can indeed read
>mode out parameters: the access value of the actual is copied into the
>formal, so you get a meaningful value coming in even though the mode
>is out. See RM 6.4.1{12,13}
So to catch bugs at an early time, given
    type Handle_Type is access ...
    procedure p(x : some_stuff;  Handle : out Handle_Type);
one should
    Handle := null;
    p(y, Handle);
otherwise a supposedly new object at Handle.all may actually be
an old object.  That must be fun to debug.