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From: "Randy Brukardt" <randy@rrsoftware.com>
Newsgroups: comp.lang.ada
Subject: Re: How to access this package written in C?
Date: Tue, 27 Apr 2010 17:29:14 -0500
Organization: Jacob Sparre Andersen
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Date: 2010-04-27T17:29:14-05:00
List-Id: <comp.lang.ada>

...
>> I use this:
>>
>>     subtype Void_Ptr is System.Address;
>
> I have sometimes used
>
>      type Void is null record;
>      pragma Convention (Void, C);
>      type Void_Ptr is access all Void;
>      pragma Convention (Void_Ptr, C);

Most of the time, I've avoided any version of void* and simply written 
overloadings for each type that I needed (using in out parameters if 
possible, or access parameters if I needed the function result). That only 
works of course when the number of types that you need is limited, and it's 
not as flexible as some more direct mapping.

But void* is exactly the opposite of strong typing, and it simply doesn't 
fit well into the Ada type model. So avoiding it if possible is the best 
approach.

                        Randy.