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From: "Ayende Rahien" <Dont@spam.me>
Newsgroups: comp.lang.ada
Subject: Re: Problem understanding procedure Adjust(.
Date: Sun, 8 Apr 2001 14:04:40 +0200
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"Jeffrey Carter" <jrcarter@acm.org> wrote in message
news:3ACFCCC6.9B4C9162@acm.org...
> Ayende Rahien wrote:
> >
> > As far as I understand, this procedure [Adjust] is called if I do
assignment on
> > stacks (which is what this package is about).
> > If I got it correctly, when I do:
> > stack1 := stack2;
> > The Adjust procedure will be called.
>
> To fully understand what happens here (assignment to a variable of a
> controlled type), first Finalize is called with Stack1 as its actual
> parameter ("Stack1 is finalized."). The Stack2's bit pattern is copied
> into Stack1's memory space ("assignment"). Then Adjust is called with
> Stack1 as its actual parameter ("Stack1 is adjusted.").
>
> So, it the stack type is implemented as a dynamically allocated linked
> list, Finalize would free the list, one node at a time. After
> assignment, both stacks would point at the same linked list. Adjust
> would then make a deep copy of Stack2's linked list for Stack1 to point
> at.

Thanks, that help understanding it.