Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!uunet!mcsun!sunic!enea!sommar
From: sommar@enea.se (Erland Sommarskog)
Newsgroups: comp.lang.eiffel
Subject: Re: Eiffel cleanup #2: Doing away with void references
Message-ID: <668@enea.se>
Date: 21 Jan 90 00:06:20 GMT
References: <227@eiffel.UUCP>
Organization: Enea Data AB, Sweden
Lines: 28

Bertrand Meyer (bertrand@eiffel.UUCP) writes:
>    - You do not really need to tell us about your new classes (although
>    we are always happy to know). The effect is conceptually that
>    of NONE inheriting from everybody else, but it does not have to
>    be that way physically.

You don't say it somewhere, but I suppose that

   inherit NONE

is illegal. Or does this mean that I inherit from every class in 
the world? Computer telepathy? :-)

>Instead of writing a.Forget, then. you now write (as in Pascal!)
>
>    a := null

Almost. "Null" is Ada. In Pascal, it's "nil".

>The test a.Void may in principle be written
>
>    a == null

Stupid question department: this is a typing error, isn't it? Or is
there really a "==" in Eiffel? Doesn't OOSC discuss why a language
should not have both "=" and "==" to avoid casual mistakes?
-- 
Erland Sommarskog - ENEA Data, Stockholm - sommar@enea.se
Unix is a virus.