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From: phil@abccam.abcl.co.uk (Phillip Yelland)
Newsgroups: comp.object,comp.lang.eiffel
Subject: Re: Reference Semantics (sic!)
Message-ID: <850@tech.abccam.abcl.co.uk>
Date: 18 Jun 91 14:12:55 GMT
Organization: Active Book Company Limited, Cambridge, UK
Lines: 28

I hope you'll forgive me if I barge in this thread, but I thought I'd throw
in my h'a'p'eth worth (two cents' worth---substitute currency as
appropriate) and a plug. I've recently defended (successfully, deo gratias)
a thesis which examines the implications of the use of references in OOL's
on their formal semantics. I wouldn't insist my findings were conclusive,
but the models I came up with did rather undermine the naive conception of
objects in such languages as neat, encapsulated parcels of state with a
finely circumscribed interface. An abbreviated summary of part of the thesis
appears in the recently-published Springer LNCS 489 
("Foundations of Object-Oriented Languages"---de Bakker, de Roever, 
Rozenberg). I'd be happy to provide copies of either of the above, 
though I'm afraid I'll need postage as my
present employer is unlikely to subsidize such activity.

I'm particularly intrigued by Kent Beck's insistence (in an earlier message)
that aliasing bugs occur in his Smalltalk code with relative infrequency.
Could he enlighten us as to how onery/hard-to-locate he actually finds such
bugs? We've recently signed off a 50K-line Smalltalk project; while they
weren't all that common, we did experience aliasing bugs that were both very
well hidden and the cause of the most bizzare consequences (windows crawling
spontaneously around the screen, etc.). (I'd not like to insist, of course,
that our Smalltalk skills are comparable to Kent's.)

--Phillip Yelland

P.S. I'm trying to locate one William Cook, late of HP Labs Palo Alto,
who---it is commonly held---has disappeared into the maw of Apple research.
Could anyone provide any pointers (:-)?