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Re: fmap(), "inverse" of Python map() function

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On Fri, Oct 5, 2012 at 3:31 PM, Ian Kelly <ian.g.kelly@gmail.com> wrote:
> On Fri, Oct 5, 2012 at 2:19 PM, vasudevram <vasudevram@gmail.com> wrote:
>>
>> http://jugad2.blogspot.in/2012/10/fmap-inverse-of-python-map-function.html
>
> Your fmap is a special case of reduce.
>
> def fmap(functions, argument):
>     return reduce(lambda result, func: func(result), functions, argument)

In a more functional style, you could also use reduce to compose the
functions before applying them:

def compose(f, g):
    return lambda x: f(g(x))

def fmap(functions):
    return reduce(compose, reversed(functions))

# Allowing you to then do:
result = fmap(functions)(argument)

Cheers,
Ian

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fmap(), "inverse" of Python map() function vasudevram <vasudevram@gmail.com> - 2012-10-05 13:19 -0700
  Re: fmap(), "inverse" of Python map() function Ian Kelly <ian.g.kelly@gmail.com> - 2012-10-05 15:31 -0600
  Re: fmap(), "inverse" of Python map() function Ian Kelly <ian.g.kelly@gmail.com> - 2012-10-05 15:43 -0600
  Re: fmap(), "inverse" of Python map() function Devin Jeanpierre <jeanpierreda@gmail.com> - 2012-10-05 18:52 -0400
  Re: fmap(), "inverse" of Python map() function Ian Kelly <ian.g.kelly@gmail.com> - 2012-10-05 17:24 -0600
  Re: fmap(), "inverse" of Python map() function Devin Jeanpierre <jeanpierreda@gmail.com> - 2012-10-05 19:30 -0400
    Re: fmap(), "inverse" of Python map() function vasudevram <vasudevram@gmail.com> - 2012-10-06 11:57 -0700
      Re: fmap(), "inverse" of Python map() function vasudevram <vasudevram@gmail.com> - 2012-10-06 15:07 -0700
      Re: fmap(), "inverse" of Python map() function vasudevram <vasudevram@gmail.com> - 2012-10-06 15:07 -0700
    Re: fmap(), "inverse" of Python map() function vasudevram <vasudevram@gmail.com> - 2012-10-06 11:57 -0700

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