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From: Stephan Heinemann <zombie@cs.tu-berlin.de>
Newsgroups: comp.lang.ada
Subject: Re: automatic tag conversion?
Date: 23 May 2003 23:57:49 GMT
Organization: Technische Universitaet Berlin, Deutschland
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Stephan Heinemann <zombie@cs.tu-berlin.de> wrote:

> t: Tag;
> subvar: Subtype;
> ...
> t := supervar'Tag;
> subvar := t'convert(supervar); -- convert(t, supervar)
> polymorphic(subvar);

Of course I don't know what the concrete Subtype is and I don't wanna
know. Therefore the code snippet is wrong. I meant:

polymorphic(t'convert(supervar))

or better and safer (because t may describe a Type not within Supertype)

polymorphic(supervar'TagType)

It is not my lazyness, but I'd like to extend my code without updating
conditionals on Strings. For every new Subtype of Supertype I not only
need to overload the polymorphic procedure but also a String comparation.

Thanks,
Stephan