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From: bobduff@world.std.com (Robert A Duff)
Subject: Re: Multiple Type Interfaces
Message-ID: <E4qo0K.IFJ@world.std.com>
Organization: The World Public Access UNIX, Brookline, MA
References: <JSA.97Jan16141937@alexandria> <32EA52FA.1CF9@jmpstart.com> <6PbObMf-3RB@herold.franken.de> <32EE352A.167EB0E7@cis.ohio-state.edu>
Date: Tue, 28 Jan 1997 22:05:08 GMT
Lines: 18
Xref: glinda.oz.cs.cmu.edu comp.lang.eiffel:17864 comp.lang.ada:56706 comp.lang.c++:243843 comp.lang.smalltalk:50237 comp.object:60471

In article <32EE352A.167EB0E7@cis.ohio-state.edu>,
Dave Gibson  <dgibson@cis.ohio-state.edu> wrote:
>Clearly packages exporting multiple tagged types would not fit the
>common OO model in which the concepts of "class" and program type are
>tightly coupled.  Nevertheless, why not define a language so components
>can export multiple types which may be extended in other related
>"derived" components?  Was this ever considered?  Was it just not
>considered the OO way by Ada95 language designers?  Perhaps it would be
>extremely complicated to implement with little perceived gain.  I'd
>appreciate any comments on this topic.

I've pondered this idea a little bit, since Ada 95 was designed.  It
sounds like it might be a good idea, but might also introduce a lot of
complexity.  I didn't really think it all through, though.  I don't know
if Tucker ever thought about it this way, before I joined the Ada 9X
project.

- Bob
