TRUE and FALSE

[Alex Martelli]

mtr at ukc.ac.uk (M.T.Russell) writes:

>In article <3686 at goanna.cs.rmit.oz.au> ok at 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
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