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From: drw@culdev1.UUCP (Dale Worley)
Newsgroups: comp.lang.misc,comp.software-eng
Subject: software ICs vs. libraries
Message-ID: <1755@culdev1.UUCP>
Date: Tue, 17-Nov-87 15:57:39 EST
Article-I.D.: culdev1.1755
Posted: Tue Nov 17 15:57:39 1987
Date-Received: Thu, 19-Nov-87 23:39:10 EST
Organization: Cullinet Software, Westwood, MA, USA
Lines: 21
Xref: mnetor comp.lang.misc:900 comp.software-eng:74

arny@wayback.UUCP (Arny B. Engelson) writes:
| In article <1716@culdev1.UUCP>, drw@culdev1.UUCP (Dale Worley) writes:
| > The other important feature that object-oriented systems need
| > (Objective-C has it, I don't know of C++ does) is that one can build
| > two objects that present the same external interface, but for which
| > the method-routines are different.
| This concept is also present in Ada.  The implementation of an object
| (such as a queue, stack, or anything else) is separated from its external
| interface.  Combine this with generics and overloading and you can create
| a pretty flexible library of "objects".

True, but in Ada, the compiler has to be able to figure out which
implementation of a given abstract object is being dealt with.  In
object-oriented languages, this only has to be determinable at
runtime.

Dale
-- 
Dale Worley    Cullinet Software      ARPA: culdev1!drw@eddie.mit.edu
UUCP: ...!seismo!harvard!mit-eddie!culdev1!drw
If you get fed twice a day, how bad can life be?