From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: fac41,9a0ff0bffdf63657 X-Google-Attributes: gidfac41,public X-Google-Thread: 1108a1,9a0ff0bffdf63657 X-Google-Attributes: gid1108a1,public X-Google-Thread: f43e6,9a0ff0bffdf63657 X-Google-Attributes: gidf43e6,public X-Google-Thread: 103376,4b06f8f15f01a568 X-Google-Attributes: gid103376,public From: "Robert Martin" Subject: Re: Software landmines (loops) Date: 1998/09/05 Message-ID: <6ssnd4$hd7$1@hirame.wwa.com>#1/1 X-Deja-AN: 388289085 References: <35f23ce2.7649859@news.erols.com> <6snn1b$c90$1@hirame.wwa.com> <35ef7dff.24318728@news.erols.com> <35f79e53.98130474@news.erols.com> <35F0B75E.F259FCE6@s054.aone.net.au> <6srcsl$qeo$1@hirame.wwa.com> <35F1B862.C1FFA000@s054.aone.net.au> X-MimeOLE: Produced By Microsoft MimeOLE V4.72.2106.4 Organization: WorldWide Access - Midwestern Internet Services - www.wwa.com Newsgroups: comp.lang.eiffel,comp.object,comp.software-eng,comp.lang.ada Date: 1998-09-05T00:00:00+00:00 List-Id: Loryn Jenkins wrote in message <35F1B862.C1FFA000@s054.aone.net.au>... >> There are two aspects to dependency management. One is to isolate those >> things which ought not depend upon each other. The other is to associate >> those things that ought to be associated. i.e. the old duo of cohesion and >> coupling. Your nicely worded phrase "conceptually modelling coherent sets >> of behaviors" is a good way of expressing the cohesion side of the equation; >> and I, of course, have no quarrel with it. Objects, after all, ought to >> consist of conceptually cohesive groupings of functions and data. Object >> models, on the other hand, should consist of an interelated set of such >> objects which have been decoupled as much as possible. > >Well ... decoupled appropriately. Of course! >Perhaps this is simply a difference in emphasis. Obviously, you run into >trouble when you have bidirectional dependencies everywhere. Obviously, >you run into trouble if you have cyclic dependencies between clusters. Absolutely. You also run into trouble when you have high level concepts depending upon implementation details. >This is an extremely important aspect of architecture. It is probably the most important aspect of software archictecture. >It just doesn't seem to me to be one of the fundamental, driving forces >of OO. (OO does enable it nicely, though.) Agreed, it is one of the fundemental driving forces of software engineering; and there have been many different approaches to addressing that force. OO is just one such approach. It is also one of the most successful approaches. Robert C. Martin | Design Consulting | Training courses offered: Object Mentor | rmartin@oma.com | Object Oriented Design 14619 N Somerset Cr | Tel: (800) 338-6716 | C++ Green Oaks IL 60048 | Fax: (847) 918-1023 | http://www.oma.com "One of the great commandments of science is: 'Mistrust arguments from authority.'" -- Carl Sagan