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From: Brian Rogoff <bpr@shell5.ba.best.com>
Subject: Re: signatures
Date: 1999/08/01
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Newsgroups: comp.lang.ada
Date: 1999-08-01T00:00:00+00:00
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Well, they force your types to be tagged, and to inherit from the abstract 
tagged type on which your subprograms operate; this is something generic
signature packages don't do unless you want them to. 

If I had my druthers, the next version of Ada would have something like 
Java interfaces, GNU C++ signatures, or Sather types/abstract-classes, in 
addition to the module signatures Ada has now. This introduces even more 
structural subtyping into Ada, but who said life was simple? :-)

-- Brian

On Sun, 1 Aug 1999, James S. Rogers wrote:

> While on the subject of signatures, do not overlook abstract subprograms.
> Abstract subprograms strictly enforce a signature without enforcing any
> specific impelementation.
> 
> Jim Rogers
> Colorado Springs, Colorado
> 
> 
> 
>