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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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