mullen@nrl-css@sri-unix.UUCP (07/26/83)
From: Preston Mullen <mullen@nrl-css> A couple of articles about a C language implementation extended with classes (much like Simula classes) have appeared recently. The most recent is "Adding Classes to the C Language" by Bjarne Stroustrup in Software -- Practice and Experience vol 13 No 2 February 1983. An earlier article by the same author appeared in ACM SIGPLAN notices January 1982. In the more recent article, the author (with Bell Labs in Murray Hill) says that the additions to the language have been implemented and are "now in use at close to a hundred installations". My question is, what installations? Is a compiler for this "extended C" part of any commercial Unix release? Can it be purchased separately? Is there any chance of it appearing in some future 4.Nbsd? P.S. It looks pretty nifty to me.
gwyn%brl-vld@sri-unix.UUCP (07/26/83)
From: Doug Gwyn (VLD/VMB) <gwyn@brl-vld> To the best of my knowledge "classes" are not part of any UNIX release, and indications so far have been that the C language will NOT be officially extended in this way. Classes are implemented by an additional preprocessor invoked if the #class keyword is found by cpp. It is rather easy to adapt the existing cc & cpp to run the classes preprocessor, which used to be available from its author (Bjarne Stroustrup). I don't know whether he wants to distribute it or not; presumably if he does he can post it to net.sources. There are two Bell Laboratories Computing Science Technical Reports on this subject: CSTR No. 84 "Classes: An Abstract Data Type Facility for the C Language" and CSTR No. 90 "A Set of C Classes for Co-routine Style Programming", both by Bjarne Stroustrup.
obrien@rand-unix@sri-unix.UUCP (07/26/83)
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trb@floyd.UUCP (Andy Tannenbaum) (07/26/83)
I don't think Stroustrup's class C is for sale yet, but that's not the point of this note. What I want to say here is that if you folks outside the Bell System want a certain piece of our software released for public use, you should express your interest to AT&T. I know that this is the address to get UNIX info, judging by their name, I'd think they'd know about other Bell System software too. Now that the Bell System is deregulated, I would think that if the world was beating a path to their door that they'd do something about selling the product in demand. Technology Licensing Manager American Telephone and Telegraph Co. P.O. Box 25000 Greensboro, North Carolina 27420 919-697-6530 This used to be a Western Electric group which has moved over to AT&T within the past two years (the same people who always dispensed UNIX for WECo). Andy Tannenbaum Bell Labs Whippany, NJ (201) 386-6491
dan@bbncd@sri-unix.UUCP (07/28/83)
From: Dan Franklin <dan@bbncd>
There is no connection between Stroustrup's work and Brad Cox's. Cox's work,
originally done at ITT as OOPC, essentially embeds some of the Smalltalk
programming language ideas in C; it provides a more "dynamic" programming
environment, in which programs can perform operations on data objects ("send
messages") without knowing at compile time precisely what objects are going to
be involved. Stroustrup's classes are entirely a compile-time construct, which
means that they are less flexible, but also less expensive (i.e., little or no
runtime overhead, as opposed to Cox's system which has a fancy, somewhat more
expensive subroutine call for sending messages to objects).
Dan Franklin