[Tutor] Writing the Map function as a oneliner

[Alan Gauld]

On 07/11/11 23:32, Rafael Turner wrote:
> Hello,
>
> I am trying to write the map function as a oneliner....
> But I would like to make recursive version. Here is what I was thinking:
>
> I can write map as
>
> def pyMap(F,li):
>      if li == []:
>          return []
>      else:
>          return [F(li[0])] + map2(F, li[1:])
>

Using the conditional expression it is nearly trivial to
convert your function to a one-liner:


def pyMap(F,li):
     return [] if li == [] else [F(li[0])] + pyMap(F,li[1:])

which becomes

pyMap = lambda F, li: [] if li == [] else [F(li[0])] + pyMap(F,li[1:])


HTH,

-- 
Alan G
Author of the Learn to Program web site
http://www.alan-g.me.uk/