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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: pointer questions
Date: 27 Oct 2005 10:14:40 -0400
Organization: The World Public Access UNIX, Brookline, MA
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Szymon Guz <alpha@skynet.org.pl_WITHOUT> writes:

> Well, that's how I thought but I wanted to ask. The problem that I want
> to solve is how to create a property in type like that ones in
> Delphi|Builder, so I have defined the property name, value, read and
> write functions. I thought that it could be done by defining a generic
> structure like this:
> 
> Name
> Value
> Get_Function
> Set_Function
> 
> when Value is a pointer to value, Get and Set are pointers to function
> for setting and getting the value. That's why I thought about universal
> variable pointer.

I'm not sure I fully understand what you're trying to do, but I suspect
you can do it with a hierarchy of tagged types.  You will have an
access-to-class-wide type, which is sort of like "void *", but it's
safe.

Alternatively, a generic package might do what you want.
You would have one instance for each type of Value you
want to store.  This method might be safer, but less flexible.

- Bob