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From: Mats Weber <Mats.Weber@elca-matrix.ch>
Subject: Re: win32ada design question/problem
Date: 1998/11/16
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Newsgroups: comp.lang.ada
Date: 1998-11-16T00:00:00+00:00
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Tom Moran wrote:

> Win32Ada is just a thin binding to that, and Windows (based on C) uses
> the equivalent of Unchecked_Access all over.  You either swallow hard
> and do C-ish code with Ada syntax, or you hide it in a thicker
> binding.

I disagree. Windows was written in C, as was UNIX, and the same problems
would appear in a UNIX binding if it were done the same way (using fancy
access types).

I think the problem with this binding is the inappropriate use of
general access types, because:

- they encourage using global declarations for the parameters (and this
is actually happening: see the examples), when using 'Unchecked_Access
would be far better.

- they don't document what is actually being done, e.g. to pass a
string, you must pass an '(Unchecked_)Access to its first character,
which is definitely not the Ada way of doing things and could even be a
problem with an aggressive optimizer.

I think a binding done with System.Address for pointers and strings, and
Interfaces.C.Int for integers, would be far better. It's the way thin
bindings were done in Ada 83 and it's a method that has always worked
fine and does not have the general access type approach's problems.