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Re: [r6rs-discuss] [Scheme-reports] redefining eqv?
Peter Kourzanov scripsit:
> > Programmers are encouraged to substitute
> > a different structural-equality predicate if EQUAL? doesn't suit their
> > needs: it is not primitive.
> Exactly. And how are they are supposed to branch on the outcome of
> their brand-new predicate? Redefine their own special (case)?
CASE doesn't use EQUAL?, so it's irrelevant; it uses EQV?, which as
I say is object identity.
> > The proposed EQUAL=? will be like EQUAL, but will employ = rather than
> > EQV? to compare numbers.
> So, the list is growing already...
Yes, and it's really unbounded. As I say, the existence and properties
of EQUAL? are merely historical. The least "jewel-like" thing about
Scheme is its standard library.
John Cowan cowan@x http://ccil.org/~cowan
Sound change operates regularly to produce irregularities;
analogy operates irregularly to produce regularities.
--E.H. Sturtevant, ca. 1945, probably at Yale
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