Re: Associativity paradox in functional expressions

From	"Pascal J. Bourguignon" <pjb@informatimago.com>
Newsgroups	comp.lang.functional, comp.lang.lisp, comp.lang.scheme, comp.programming, comp.emacs
Subject	Re: Associativity paradox in functional expressions
Date	2012-11-06 07:28 +0100
Organization	Informatimago
Message-ID	<87ip9j8ctc.fsf@informatimago.com> (permalink)
References	(1 earlier) <9972e570-2504-4401-8de8-49eb1929fdfd@c17g2000yqe.googlegroups.com> <87pq3wqftc.fsf@voyager.informatimago.com> <3dd68e98-9889-4287-a352-3c7c25a3284e@d17g2000vbv.googlegroups.com> <87liejml8j.fsf@informatimago.com> <e2187fc0-9ccf-4fb8-8f1f-afd7df99964f@x21g2000vbg.googlegroups.com>

Cross-posted to 5 groups.

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Rivka Miller <rivkaumiller@gmail.com> writes:

> Are you saying that the Late Dr McCarthy, after thinking of lisp in
> terms of lambda calculus (and its associated currying), nevertheless
> implemented it in terms of variadic non-curried functions? Thus the
> turing machine replacement that lambda calculus is supposed to be,
> does not need any currying to be a replacement of turing machine - in
> the sense of computability?

Yes.  John McCarthy didn't understand lambda calculus at the time. He
just used the lambda notation for his functions, but they differed
greately, notably  in that he used dynamic binding instead of lexical
binding.


> How would the "(funcall g g n)"  and  "(funcall f f (1- n))" in the
> function advanced by the OP supposed to be associated if currying were
> available?
>
> ((lambda(g n) (funcall g g n))
>  (lambda(f n)
>    (if (zerop n) 1
>      (* n (funcall f f (1- n)))))
>  4 )

Well, in lisp there are parentheses to imply the order of evaluation…

-- 
__Pascal Bourguignon__
http://www.informatimago.com

Thread

Re: Associativity paradox in functional expressions Totaram Sanadhya <swami.totaram.sanadhya@gmail.com> - 2012-10-31 00:24 -0700
  Re: Associativity paradox in functional expressions Barb Knox <see@sig.below> - 2012-10-31 21:14 +1300
    Re: Associativity paradox in functional expressions Totaram Sanadhya <swami.totaram.sanadhya@gmail.com> - 2012-10-31 10:34 -0700
      Re: Associativity paradox in functional expressions Dirk Thierbach <dthierbach@usenet.arcornews.de> - 2012-10-31 23:36 +0100
  Re: Associativity paradox in functional expressions Nils M Holm <news2009@t3x.org> - 2012-10-31 09:21 +0000
  Re: Associativity paradox in functional expressions "Pascal J. Bourguignon" <pjb@informatimago.com> - 2012-11-02 14:45 +0100
    Re: Associativity paradox in functional expressions Rivka Miller <rivkaumiller@gmail.com> - 2012-11-02 18:59 -0700
      Re: Associativity paradox in functional expressions "Pascal J. Bourguignon" <pjb@informatimago.com> - 2012-11-03 04:14 +0100
        Re: Associativity paradox in functional expressions Rivka Miller <rivkaumiller@gmail.com> - 2012-11-05 16:53 -0800
          Re: Associativity paradox in functional expressions "Pascal J. Bourguignon" <pjb@informatimago.com> - 2012-11-06 07:28 +0100
            Re: Associativity paradox in functional expressions Barb Knox <see@sig.below> - 2012-11-08 17:35 +1300
              Re: Associativity paradox in functional expressions Aatu Koskensilta <aatu.koskensilta@uta.fi> - 2012-11-08 07:42 +0200
                Re: Associativity paradox in functional expressions "Pascal J. Bourguignon" <pjb@informatimago.com> - 2012-11-08 21:47 +0100
                Re: Associativity paradox in functional expressions Barb Knox <see@sig.below> - 2012-11-10 15:13 +1300

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