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Date: Fri, 23 Apr 2004 18:33:05 -0400
From: Hyman Rosen <hyrosen@mail.com>
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Subject: Re: OOP Language for OS Development
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Date: 2004-04-23T18:33:05-04:00
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Brian_Heilig wrote:
> Either I don't understand your post or you are mistaken. If the
> derived class conforms to (inherits from) the parameter's type then
> there is no problem.

In Eiffel, Derived::Foo(Derived) overrides Base::Foo(Base).
That means that if you have a Base object, and you call
some_base_reference.Foo(some_other_base_reference), the call
looks correct, but if some_base_reference is really a Derived
and some_other_base_reference is not a Derived, you have an
error.

It's a horrible misfeature, but its proponents cling to it
tenaciously, and they have spent years trying to figure out
workarounds so that the errors can be caught.