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How to write this as a list comprehension?

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Hi,

I am looking for an elegant way to write the following code as a list
comprehension:

labels = []
for then, name in mylist:
    _, mn, dy, _, _, _, wd, _, _ = localtime(then)
    labels.append(somefunc(mn, day, wd, name))

So mylist is a list of tuples, the first member of the tuple is a time
(as epoch offset) and I neeed to apply a function on some fields of the
localtime of it.

I could define a auxiliary function like:

def auxfunc(then, name):
    _, mn, dy, _, _, _, wd, _, _ = localtime(then)
    return somefunc(mn, day, wd, name)

and then use 
[auxfunc(then, name) for then, name in mylist]

or even
[auxfunc(*tup) for tup in mylist]

But defining the auxfunc takes away the elegance of a list comprehension. I would like to integrate the unpacking of localtime() and calling somefunc within the list comprehension, but I don't see a simple way to do that.

somefunc(mn, day, wd, name) for _, mn, dy, _, _, _, wd, _, _ in [localtime(then)] 
(i.e. using a list comprehension on a one element list to do the variable shuffling) 
works but I don't find that very elegant.

labels = [somefunc(mn, day, wd, name) 
            for then, name in mylist
            for _, mn, dy, _, _, _, wd, _, _ in [localtime(then)]]

Python misses a 'where' or 'let'-like construction as in Haskell.

Anybody has a more elegant solution?
-- 
Piet van Oostrum <piet@vanoostrum.org>
WWW: http://pietvanoostrum.com/
PGP key: [8DAE142BE17999C4]

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Thread

How to write this as a list comprehension? Piet van Oostrum <piet@vanoostrum.org> - 2014-01-18 00:19 +0100
  Re: How to write this as a list comprehension? Dan Stromberg <drsalists@gmail.com> - 2014-01-17 15:49 -0800
  Re: How to write this as a list comprehension? Rustom Mody <rustompmody@gmail.com> - 2014-01-17 19:25 -0800
    Re: How to write this as a list comprehension? Piet van Oostrum <piet@vanoostrum.org> - 2014-01-18 11:00 +0100
  Re: How to write this as a list comprehension? Peter Otten <__peter__@web.de> - 2014-01-18 09:36 +0100
    Re: How to write this as a list comprehension? Rustom Mody <rustompmody@gmail.com> - 2014-01-18 07:20 -0800
      Re: How to write this as a list comprehension? Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2014-01-18 18:00 +0200
        Re: How to write this as a list comprehension? "Rhodri James" <rhodri@wildebst.org.uk> - 2014-01-19 23:41 +0000
          Re: How to write this as a list comprehension? Piet van Oostrum <piet@vanoostrum.org> - 2014-01-20 12:02 +0100
            Re: How to write this as a list comprehension? Rustom Mody <rustompmody@gmail.com> - 2014-01-20 03:47 -0800
  Re: How to write this as a list comprehension? matej@ceplovi.cz (Matěj Cepl) - 2014-01-18 11:57 +0100
  Re: How to write this as a list comprehension? Alain Ketterlin <alain@dpt-info.u-strasbg.fr> - 2014-01-18 12:53 +0100
    Re: How to write this as a list comprehension? Piet van Oostrum <piet@vanoostrum.org> - 2014-01-18 18:40 +0100
  Re: How to write this as a list comprehension? John Allsup <pydev@allsup.co> - 2014-01-19 01:24 +0000
    Re: How to write this as a list comprehension? Piet van Oostrum <piet@vanoostrum.org> - 2014-01-19 23:06 +0100

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