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: f43e6,9a0ff0bffdf63657 X-Google-Attributes: gidf43e6,public X-Google-Thread: 1108a1,9a0ff0bffdf63657 X-Google-Attributes: gid1108a1,public X-Google-Thread: 103376,4b06f8f15f01a568 X-Google-Attributes: gid103376,public From: "Robert Martin" Subject: Re: Software landmines (loops) Date: 1998/09/04 Message-ID: <6sor5t$5i8$1@hirame.wwa.com>#1/1 X-Deja-AN: 387836089 References: <6sbuod$fra$1@hirame.wwa.com> <35f51e53.48044143@ <904556531.666222@miso.it.uq.edu.au> <6sgror$je8$3@news.indigo.ie> <6sh3qn$9p2$1@hirame.wwa.com> <6shbca$66c$1@news.indigo.ie> <6shhq7$lut$1@hirame.wwa.com> <6sjbso$1lk$2@news.indigo.ie> <6sjijg$36r$1@hirame.wwa.com> <6skhcm$1dr$2@news.indigo.ie> <6skqf3$9g0$1@hirame.wwa.com> <35f1f9fe.9111641@news.erols.com> <35f23ce2.7649859@news.erols.com> <6snn1b$c90$1@hirame.wwa.com> <35ef7dff.24318728@news.erols.com> 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: 1998-09-04T00:00:00+00:00 List-Id: Ell wrote in message <35ef7dff.24318728@news.erols.com>... >"Robert Martin" wrote: > >> >>Ell wrote in message <35f23ce2.7649859@news.erols.com>... >> >>> >>>Think "avoid unstructured control flow", and not "avoid [creating code >>>which has multiple exits]". > >>You had best define 'unstructured' in this context. Dijkstra's definition >>of 'unstructured control flow' is control flow that does not conform >>precisely to the four standard sequencing elements {sequence, selection, top >>exit loop, bottom exit loop}, all of which have a single entry and a single >>exit. > >Where is this documented? Where has Dijkstra stated that flow control >must conform precisely to the 4 specific elements you mention? Elliott, I've already answered this question several times. I can only assume that you reason you keep asking this is that you don't want to look it up for yourself on the off chance that you might find it to be true. Let me assure you, if you read the citings I have given you so many times you *will* find that Dijkstra recommended four, and only four, control elements. >Please refer to relevant citations to back up this assertion. I have >seen nothing that Dijkstra refers to explicitly about se/se on other >than what you quoted about flowcharts. And this everyone knows is how >to create flowcharts on a page - one entry point, one exit. Then clearly you have not read much of Dijkstra. The citation you want is the citation I have given you many many times. Go look it up Elliott. 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 > >Elliott