Path: utzoo!attcan!uunet!mcsun!ukc!edcastle!dcl-cs!aber-cs!athene!pcg From: pcg@cs.aber.ac.uk (Piercarlo Grandi) Newsgroups: comp.object Subject: Re: Teaching an Object-Oriented Pro Message-ID: Date: 17 Sep 90 16:08:51 GMT References: <90@ <77500057@m.cs.uiuc.edu> Sender: pcg@aber-cs.UUCP Organization: Coleg Prifysgol Cymru Lines: 73 Nntp-Posting-Host: odin In-reply-to: johnson@m.cs.uiuc.edu's message of 16 Sep 90 04:37:00 GMT On 16 Sep 90 04:37:00 GMT, johnson@m.cs.uiuc.edu said: johnson> However, I would like to quarrel with his characterization of johnson> Smalltalk. C++ is by far the most popular object-oriented johnson> language for commercial use in the U.S. However, Smalltalk johnson> might very well be in second place. I may be mistaken, but I have not yet seen that many *products* being sold that were implemented in Smalltalk, either -80 or /V. On the other hand I would agree that a lot of companies use Smalltalk for *internal* purposes, that range from prototyping (most often) to AI and user interfaces. johnson> Eiffel or Objective-C might have second place, but not by much. Well, I have seen papers on several *very large* systems being commercially developed and sold in Objective C and Eiffel. johnson> I know of quite a few companies building products in Smalltalk. This I cannot know -- I am far removed from the scene, unfortunately. I do know of some products in Smalltalk, now that I think of it. Several packages from Xerox, and of course the development environments from ParcPlace Systems. Also, I have heard rumours about financial packages, but people that do these are usually fairly secretive. johnson> Also, ParcPlace Smalltalk is not expensive for universities johnson> because of their site license. The site license makes it quite johnson> reasonable to teach classes with it. Well, I have just been told about their site licensing program. You pay a couple grand and you have a campus wide license for one CPU type (e.g. Sun-3 or Intel or...). Not a bad deal. johnson> I like to use Smalltalk to teach object-oriented programming because johnson> the class library makes a great set of examples. The programming johnson> environment makes programming fun, which always helps a class. On the johnson> other hand, lots of other o-o languages come with good class libraries johnson> and a nice programming environment. Yes, but admittedly nothing is quite like Smalltalk in that respect -- it's the Rolls-Royce of the OO languages. I have seen an Objective C environment that competes with it though. johnson> Unfortunately, C++ is not one of johnson> them. Uhm. Uhm. For all its defects, C++ surely has a large collection of class libraries. Its user programming environment is the standard Unix one, which is fairly tolerable. There also exist several C++ browsers, some for GNU Emacs, some stand-alone, like Brown Unviersity's one. Nothing as smooth as Smalltalk's, admittedly. Frankly, my reply was slanted towards the needs of somebody who clearly wanted to provide more job oriented training than ivory tower education, and without spending much money. I will be the first to admit that Smalltak, for understanding what OO is all about, is vastly better than C++, but for job-related experience, the latter is on another plane. If the only gauge is to be insight/education in OO *languages*, then I would lean towards using something basd on Scheme on one hand, or Simula 67 (or, and I did not mention it because implementations are not that easy to come by, BETA). If OO *environments* is the gauge, then there is little alternative to Smalltalk, but for maybe Objective-C, e.g. as in the very beautiful environment developed in a joint HP/Stanford project, which is highly competitive with the Smalltalk one. -- Piercarlo "Peter" Grandi | ARPA: pcg%uk.ac.aber.cs@nsfnet-relay.ac.uk Dept of CS, UCW Aberystwyth | UUCP: ...!mcsun!ukc!aber-cs!pcg Penglais, Aberystwyth SY23 3BZ, UK | INET: pcg@cs.aber.ac.uk