Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!rutgers!deejay!gear!cadlab!staff From: staff@cadlab.sublink.ORG (Alex Martelli) Newsgroups: comp.lang.c Subject: Re: TRUE and FALSE Message-ID: <262@cadlab.sublink.ORG> Date: 6 Sep 90 17:42:28 GMT References: <5398@harrier.ukc.ac.uk> <3686@goanna.cs.rmit.oz.au> <5409@harrier.ukc.ac.uk> Organization: CAD.LAB, Bologna, Italia Lines: 20 mtr@ukc.ac.uk (M.T.Russell) writes: >In article <3686@goanna.cs.rmit.oz.au> ok@goanna.cs.rmit.oz.au (Richard A. O'Keefe) writes: ...omitted... >>In Pascal FALSE < TRUE is allowed, meaningful, and true. >I can't see any use for this, but I don't have any violent objection An use is to implement the "MATERIAL IMPLICATION" operator of propositional calculus; "a IMPLIES b" can be written "a <= b" under Pascal's ordering (yup, as another poster points out, it can also be written "b OR NOT a", but then why have an AND operator at all, since it "a AND b" can be easily rewritten "NOT (NOT a OR NOT b)"...?-). -- Alex Martelli - CAD.LAB s.p.a., v. Stalingrado 45, Bologna, Italia Email: (work:) staff@cadlab.sublink.org, (home:) alex@am.sublink.org Phone: (work:) ++39 (51) 371099, (home:) ++39 (51) 250434; Fax: ++39 (51) 366964 (work only; any time of day or night).