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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: Preventing Unchecked_Deallocation?
Date: Tue, 07 Feb 2012 16:30:18 -0500
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Date: 2012-02-07T16:30:18-05:00
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Simon Belmont <sbelmont700@gmail.com> writes:

> On Feb 7, 6:42�am, Gautier write-only <gautier_niou...@hotmail.com>
> wrote:
>
>> ...in 99% of the cases you don't even need accesses at all

I'm not sure what that means.  99% of what cases?  I mean,
there are lots of "cases" where you would use an integer,
or an array, or a procedure, or an if_statement, rather
than an access type.

Anyway, whether pointers are needed rarely or often depends
on the application area.

> Can you explain this further?  I can envision many more than 1% of
> situations where they would be needed, which means I am probably still
> stuck in another languages mentality.  If X and Y must both call
> primitive operations of Z, then what other options are there?

I don't understand that last sentence.  You don't need pointers
(access types) to call primitive operations.

In Ada, you need pointers if you want to create linked heap-allocated
data structures.  In the kinds of program I write, that happens often.
You also need pointers if you want to implement size-changing objects.
Not for much else.

It's often a good idea to hide the pointers away in a package,
rather than scattering them all over the program.

- Bob