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Re: Functional Programming and python

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rusi writes:

> Without resorting to lambdas/new-functions:
>  With functools.partial one can freeze any subset of a
>  function(callable's) parameters.
>
>  In Haskell one can only freeze the first parameter or at most with
>  a right section the second

You have an f of type A -> B -> C -> D -> E in Haskell, you can freeze
the first three parameters by calling it with three arguments. These
are equivalent:

f a b c d
(f a b c) d
(f a b) c d
(f a) b c d

So it's any initial sequence of arguments, not just the first.

And I thought such types were preferred over A * B * C * D -> E in
Haskell, so you tend to get this for free. Not sure of the syntax here
- it's been long since I did anything at all with Haskell.

A difference seems to be that in Python, a call can refer to named
parameters. This gives functools.partial some power over Haskell.

Another difference is that the value of functools.partial is always a
function that needs to be called with the remaining arguments, even if
there are none. Both the creation and the evaluation of the curried
functions just happens in Haskell.

(I also think that the word "currying" used to refer to what Haskell
does and it's an extension to use it to mean any partial evaluation.)

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Thread

Where to suggest improvements in the official Python documentation? Aseem Bansal <asmbansal2@gmail.com> - 2013-08-03 10:53 -0700
  Re: Where to suggest improvements in the official Python documentation? Joel Goldstick <joel.goldstick@gmail.com> - 2013-08-03 14:23 -0400
  Re: Where to suggest improvements in the official Python documentation? Terry Reedy <tjreedy@udel.edu> - 2013-08-03 16:43 -0400
    Re: Where to suggest improvements in the official Python documentation? Aseem Bansal <asmbansal2@gmail.com> - 2013-08-04 09:30 -0700
      Re: Where to suggest improvements in the official Python documentation? Joel Goldstick <joel.goldstick@gmail.com> - 2013-08-04 14:34 -0400
        Re: Where to suggest improvements in the official Python documentation? Aseem Bansal <asmbansal2@gmail.com> - 2013-08-20 07:22 -0700
          Re: Where to suggest improvements in the official Python documentation? Joel Goldstick <joel.goldstick@gmail.com> - 2013-08-20 10:57 -0400
      Functional Programming and python rusi <rustompmody@gmail.com> - 2013-09-22 19:21 -0700
        Re: Functional Programming and python Vito De Tullio <vito.detullio@gmail.com> - 2013-09-23 20:24 +0200
          Re: Functional Programming and python Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2013-09-24 10:06 +0300
          Re: Functional Programming and python rusi <rustompmody@gmail.com> - 2013-09-24 00:08 -0700
            Re: Functional Programming and python Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2013-09-24 10:42 +0300
              Re: Functional Programming and python rusi <rustompmody@gmail.com> - 2013-09-24 05:14 -0700
                Re: Functional Programming and python Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2013-09-24 17:51 +0300
                Re: Functional Programming and python rusi <rustompmody@gmail.com> - 2013-09-24 08:07 -0700
                Re: Functional Programming and python Chris Angelico <rosuav@gmail.com> - 2013-09-25 01:26 +1000
                Re: Functional Programming and python rusi <rustompmody@gmail.com> - 2013-09-24 10:25 -0700
        Re: Functional Programming and python Franck Ditter <nobody@nowhere.org> - 2013-09-30 19:04 +0200
          Re: Functional Programming and python Chris Angelico <rosuav@gmail.com> - 2013-10-01 03:17 +1000
          Re: Functional Programming and python Neil Cerutti <neilc@norwich.edu> - 2013-09-30 18:36 +0000
            Re: Functional Programming and python Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-10-01 00:14 +0000
              Re: Functional Programming and python Neil Cerutti <neilc@norwich.edu> - 2013-10-01 13:59 +0000
          Re: Functional Programming and python Piet van Oostrum <piet@vanoostrum.org> - 2013-09-30 14:55 -0400
            Re: Functional Programming and python Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2013-09-30 22:37 +0200
              Re: Functional Programming and python Piet van Oostrum <piet@vanoostrum.org> - 2013-10-01 13:31 -0400
          Re: Functional Programming and python Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2013-09-30 20:29 +0200
          Re: Functional Programming and python Tim Chase <python.list@tim.thechases.com> - 2013-09-30 16:02 -0500
          Re: Functional Programming and python Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-10-01 00:41 +0000
          Re: Functional Programming and python alex23 <wuwei23@gmail.com> - 2013-10-01 11:03 +1000
          Re: Functional Programming and python Terry Reedy <tjreedy@udel.edu> - 2013-09-30 21:03 -0400
            Re: Functional Programming and python rusi <rustompmody@gmail.com> - 2013-09-30 18:36 -0700
              Re: Functional Programming and python Chris Angelico <rosuav@gmail.com> - 2013-10-01 17:28 +1000

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