equality predicates (was Re: [plt-scheme] fractions and decimals)

From: Doug Orleans (dougo at ccs.neu.edu)
Date: Tue Jan 28 10:15:46 EST 2003

Stephen Bloch writes:
 > Now THAT's peculiar: I was under the impression that "equal?" was 
 > implied by all the other equality predicates.

It is, depending on your definition of equality predicate.  :)
The weird thing about `=' (and `string=?' et al) is that it isn't a
general predicate; `(= "foo" "bar")' doesn't return false, it raises
an error.  Similarly, `integer?' isn't a type predicate, because it's
only defined on numbers.

--dougo at ccs.neu.edu

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