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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Subject: Re: About 0Y interfaces
Newsgroups: comp.lang.ada
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Date: Tue, 18 Oct 2005 15:18:14 +0200
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On Tue, 18 Oct 2005 14:49:04 +0200, Alex R. Mosteo wrote:

> I hope someone can clarify some aspects of interfaces to me. I've read 
> the description in several places but there are some things I'm not sure 
> about.
> 
> Firstly, interfaces are purely abstract, right? There's no way to 
> provide a default/partial implementation except creating an object type 
> which implements that interface.
> 
> Secondly, we can create an object type which implements two or more 
> interfaces. But I guess there's no multiple inheritance from classes, so 
> you couldn't use two implementations of two different interfaces 
> directly when creating a new type. Is this right? You'd need to use, for 
> example, member objects and use proxy calls.

I think the answer depends on what is meant under "implementation":

1. Implementation of the values
(data implementation)

2. Implementation of the primitive operations
(type interface implementation)

3. Implementation of class-wide operations
(class interface implementation)

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de