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To: python-list@python.org
From: Terry Reedy <tjreedy@udel.edu>
Subject: Re: Is there a function that applies list of functions to a value?
Date: Fri, 30 Aug 2013 00:38:55 -0400
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Xref: csiph.com comp.lang.python:53273

On 8/29/2013 5:48 PM, fp2161@gmail.com wrote:

> Here is the generalisable version:
>
> def comp(*func):
>      def anon(x):
>          res=x
>          for f in func:
>              res=f(res)
>          return res
>      return anon

With a bit more work, one can set the __name__ and __qualname__ attributes.

import math as m

def comp(*func, name=''):
     def anon(x):
         res=x
         for f in func:
             res=f(res)
         return res
     if name:
         anon.__name__ = name
         q = anon.__qualname__.rsplit('.', maxsplit=1)
         q[1] = name
         anon.__qualname__ = '.'.join(q)
     return anon

esincos = comp(m.exp, m.sin, m.cos, name='esincos')
print(esincos)
#
<function comp.<locals>.esincos at 0x00000000033107B8>

-- 
Terry Jan Reedy