len@geac.UUCP (Leonard Vanek) (02/04/87)
In article <438@apple.UUCP> lsr@apple.UUCP (Larry Rosenstein) writes: > >To be concrete, suppose the message is Draw. Then you do need to know that >the object you send a message to can understand Draw, but you do not need >to know if it is going to draw a circle, rectangle, line, etc. > >So your program has to be correct in so far as it never confuses graphical >objects with numbers, for example. But other than that, it does not have to >keep track of the specific kind of each graphical object. The runtime >system does that for you. > >>Also, I have repeatedly heard the claim that dynamically bound languages are >>"just as fast" as static languages. OK, make me a believer. Who says so? > >Consider implementing a graphics editor in C or Pascal. (I will take >Pascal, because I am more familiar with it.) The above excerpt illustrates a situation which really bothers me about OOPS. I truly believe that there are benefits to software engineering using Object Oriented programming, but I find that out in the world of OOPS users "object oriented" and "graphical" are almost synonyms. This was obvious to me at the September OOPSLA conference where there were many papers that dealt as much with graphics as with OOPS and even more papers in which the only examples used were graphical in nature. The applications that I have in mind have very little to do with graphics because they must run on ordinary non-graphic terminals. Will OOPS buy me anything? Is there anyone out there writing REAL applications using an O-O programming language and NO GRAPHICS? --------------------------------------------------------------------- Leonard Vanek phone (416) 475-0525 Geac Computers International 350 Steelcase Rd. West Markham Ontario L3R 1B3 Canada UUCP ... {allegra,ihnp4,decvax,pyramid} !utzoo!yetti!geac!len
oster@lapis.berkeley.edu.UUCP (02/07/87)
OOP is a natural metaphor for any problem involving distributed systems. The model of a collection of objects communicating via message passing, is identical to the actual situation, where each object is implemented via a separate process running on its own processor.
segall@caip.UUCP (02/09/87)
len@geac.UUCP (Leonard Vanek) writes: > Is there anyone out there writing REAL applications using an O-O > programming language and NO GRAPHICS? Of course. I am. I don't know why _all_ the examples you saw were graphics problems, but I suspect I know why most of them were: 1) Graphics problems are very nice to implement with an o-o system, for the reasons posted; 2) It's one heck of a lot easier (and more interesting, to the casual observer) to explain and understand things when you use pictures. The arcane details of the internals of someone's application are not quite as valuable teaching tools as visual examples. My application doesn't use graphics (yet). I'm developing an object-oriented system to optimize certain computationally-intensive problems for solution on parallel computers. Smalltalk lends itself beautifully to development of this system, for all the usual reasons relating to programming environment, but there is a more important reason: The approach I'm taking to this problem is inherently object-oriented. To program this system without an o-o system would be a nightmare, and I don't think I would do it. I would either have to develop a system that doesn't really have the full flexibility I think is required, or I'd have to implement my own o-o system, which would be an unnecessary distraction and a waste of time. Ed Segall segall@caip.rutgers.edu {pyramid, seismo, ut-sally}!topaz!caip!segall