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Subject: Re: Non-philosophical definition of Eiffel?
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Date: Wed, 30 Jul 2003 04:31:55 GMT
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Date: 2003-07-30T04:31:55+00:00
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Berend de Boer wrote:
>   The implementation of virtual constructors relies on a recent
>   modification to C++, namely virtual functions' covariance.

There's no such thing as a virtual constructor in C++.
Covariant return types are not a "recent" modification
of C++ - they're in the Standard.

> Fortunately I'm not a C++ expert so I can't really asses your claim
> that the STL container libray offers the same functionality as an
> Eiffel generic container library. But I really doubt it.

Same functionality? They're containers. You put things in,
you take things out. They come out with the same type they
were put in with. The container holds things of exactly one
type, so there's no casting. If you want a polymorphic
container, you use a regular container of pointers to a
common base type.

If you're not a C++ expert but you know Ada, look up
Matthew Heaney's Charles library, which does the same kind
of thing in Ada.