Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.python > #64227

Re: How to write this as a list comprehension?

Show all headers | View raw

Piet van Oostrum <piet@vanoostrum.org> writes:

[...]
> 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]

[...]

> 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.

"let x = v in e" really is (lambda x:e)(v)

In your case:

[ (lambda na,ti : somefunc(ti[1],ti[2],ti[6],na))(name,localtime(then))
  for then,name in mylist ]

Warning: absolutely untested (not even syntax-checked).

You may also use *localtime(...) and keep underscores.

-- Alain.

Back to comp.lang.python | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

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

csiph-web