rusi rustompmody at gmail.com
Fri Jul 13 00:33:40 EDT 2012

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On Jul 11, 11:41 am, Daniel Fetchinson <fetchin... at googlemail.com>
wrote:
> funcs = [ lambda x: x**i for i in range( 5 ) ]
> print funcs[0]( 2 )
> print funcs[1]( 2 )
> print funcs[2]( 2 )
>
> This gives me
>
> 16
> 16
> 16
>
> When I was excepting
>
> 1
> 2
> 4
>
> Does anyone know why?
>
> Cheers,
> Daniel

Your expectations are reasonable.  Heres the equivalent in Haskell
from which python has taken comprehensions.
---------------------------------
GHCi, version 7.4.1: http://www.haskell.org/ghc/  :? for help

Prelude> let funcs = [ (\ x -> x ^ i)| i <- [0..4]]
Prelude> (funcs !! 0)(2)
1
Prelude> (funcs !! 1)(2)
2
Prelude> (funcs !! 2)(2)
4
Prelude>

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