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Re: I am still kinda depressed about learning forth

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Hugh Aguilar wrote:

> > (printf "below average: ~a\n"
> >   (count (curry > (average numbers)) numbers))
> > (printf "above average: ~a\n"
> >   (count (curry < (average numbers)) numbers))
> 
> You are well known (notorious) for promoting Ruby on these forums. You
> also apparently know Racket though. What are the pros and cons of
> those two languages compared to each other? If I was stranded on a
> desert island (my brain is actually somewhat similar to a desert
> island), which language should I take with me?

I can't answer that.  There is no accounting for taste.  Both languages
are excellent.  Ruby offers more brevity but lacks macros and
high-speed looping.  I use Ruby for most work that I need to perform.

> 
> BTW: I'm holding off on a Forth solution until Gavino at least tries a
> little bit on his own.
> 
> P.S. I don't know what CURRY means in the above.

Let's say we want to count the odd numbers in a list.

(count (lambda(n) (odd? n)) '(1 1 2 3 5 8))
4

We can dispense with the anonymous function (lambda) and use
odd? directly since it only needs one argument:

(count odd? '(1 1 2 3 5 8))
4

Now we want to count the numbers larger than 3:

(count (lambda(n) (< 3 n)) '(1 1 2 3 5 8))
2

How do we get rid of the ugly lambda and the parameter n?

Using currying or partial application, we convert < to a
function that needs only one argument (by supplying up front
one of the two arguments it needs).

(count (curry < 3) '(1 1 2 3 5 8))
2

This is much cleaner because there is no named parameter.

If we want to pre-supply the rightmost argument instead of the
leftmost, we use curryr.

(count (curryr > 3) '(1 1 2 3 5 8))
2

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I am still kinda depressed about learning forth quiet_lad <gavcomedy@gmail.com> - 2012-07-10 21:17 -0700
  Re: I am still kinda depressed about learning forth quiet_lad <gavcomedy@gmail.com> - 2012-07-10 21:43 -0700
  Re: I am still kinda depressed about learning forth marko <marko@marko.marko> - 2012-07-11 14:55 +1000
    Re: I am still kinda depressed about learning forth quiet_lad <gavcomedy@gmail.com> - 2012-07-10 21:57 -0700
      Re: I am still kinda depressed about learning forth marko <marko@marko.marko> - 2012-07-11 15:12 +1000
    Re: I am still kinda depressed about learning forth quiet_lad <gavcomedy@gmail.com> - 2012-07-10 22:04 -0700
    Re: I am re energized to learn forth and see how simple computers can be! quiet_lad <gavcomedy@gmail.com> - 2012-07-10 22:05 -0700
      Re: I am re energized to learn forth and see how simple computers can be! Mark Wills <markrobertwills@yahoo.co.uk> - 2012-07-11 02:08 -0700
        Re: I am re energized to learn forth and see how simple computers can be! Doug Hoffman <glidedog@gmail.com> - 2012-07-11 07:14 -0400
          Re: I am re energized to learn forth and see how simple computers can be! Mark Wills <markrobertwills@yahoo.co.uk> - 2012-07-11 04:54 -0700
            Re: I am re energized to learn forth and see how simple computers can be! marko <marko@marko.marko> - 2012-07-11 22:30 +1000
            Re: I am re energized to learn forth and see how simple computers can be! Doug Hoffman <glidedog@gmail.com> - 2012-07-11 08:35 -0400
            Re: I am re energized to learn forth and see how simple computers can be! Hannu Vuolasaho <hannu.vuolasaho@nospam.tut.fi.invalid> - 2012-07-11 14:13 +0000
              Re: I am re energized to learn forth and see how simple computers can be! Bernd Paysan <bernd.paysan@gmx.de> - 2012-07-12 22:01 +0200
            Re: I am re energized to learn forth and see how simple computers can be! Fanzo <cristianof6@gmail.com> - 2012-07-11 21:27 +0200
              Re: I am re energized to learn forth and see how simple computers can be! Doug Hoffman <glidedog@gmail.com> - 2012-07-11 16:41 -0400
                Re: I am re energized to learn forth and see how simple computers can be! quiet_lad <gavcomedy@gmail.com> - 2012-07-11 14:49 -0700
              Re: I am re energized to learn forth and see how simple computers can be! Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-07-12 01:06 +0000
              Re: I am re energized to learn forth and see how simple computers can be! Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-07-13 23:01 -0700
                Re: I am re energized to learn forth and see how simple computers can be! "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-07-14 03:28 -0400
                Re: I am re energized to learn forth and see how simple computers can be! Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-07-14 03:39 -0700
                Re: I am re energized to learn forth and see how simple computers can be! quiet_lad <gavcomedy@gmail.com> - 2012-07-17 15:54 -0700
                Re: I am re energized to learn forth and see how simple computers can be! quiet_lad <gavcomedy@gmail.com> - 2012-07-17 14:23 -0700
            Re: I am re energized to learn forth and see how simple computers can be! Doug Hoffman <glidedog@gmail.com> - 2012-07-11 16:37 -0400
          Re: I am re energized to learn forth and see how simple computers can be! quiet_lad <gavcomedy@gmail.com> - 2012-07-11 13:19 -0700
  Re: I am still kinda depressed about learning forth Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-07-15 16:57 -0700
    Re: I am still kinda depressed about learning forth Clyde Phillips <cwpjr02@gmail.com> - 2012-07-15 22:07 -0700
      Re: I am still kinda depressed about learning forth Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-07-15 22:36 -0700
    Re: I am still kinda depressed about learning forth "WJ" <w_a_x_man@yahoo.com> - 2012-07-17 13:52 +0000
      Re: I am still kinda depressed about learning forth quiet_lad <gavcomedy@gmail.com> - 2012-07-17 16:18 -0700
      Re: I am still kinda depressed about learning forth "WJ" <w_a_x_man@yahoo.com> - 2012-07-18 23:41 +0000
        Re: I am still kinda depressed about learning forth "WJ" <w_a_x_man@yahoo.com> - 2012-07-19 00:34 +0000
          Re: I am still kinda depressed about learning forth Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-07-18 21:11 -0700
            Re: I am still kinda depressed about learning forth "WJ" <w_a_x_man@yahoo.com> - 2012-07-19 06:23 +0000
              Re: I am still kinda depressed about learning forth Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-07-18 23:54 -0700
      Re: I am still kinda depressed about learning forth "WJ" <w_a_x_man@yahoo.com> - 2012-07-19 00:13 +0000
    Re: I am still kinda depressed about learning forth quiet_lad <gavcomedy@gmail.com> - 2012-07-17 16:06 -0700

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