Hey,
thanks for the help!
Yes it is part of a homework that I can't find out (I am fine with other
parts).
This is not the homework itself, just the part of it and I needed help with
it, thanks for that!
I would like to understand the solution and not only have it so I would like
to ask you:
What does the ($) at zipWith?
Thanks again!
On Sat, Apr 3, 2010 at 6:18 PM, Alexandru Scvortov
Too many points.
listbool :: [[a]] -> [[Bool]] listbool = zipWith ($) (map (map . const) (cycle [True, False]))
Cheers, Alex
On Saturday 03 April 2010 15:13:48 Edward Z. Yang wrote:
Excerpts from Maur Toter's message of Sat Apr 03 09:54:26 -0400 2010:
I am new with Haskell so I think this will be a pretty dumb question. I would like to make a function that makes this:
listbool :: [[Int]] -> [[Bool]]
in this way: listbool [[1,2],[3,4]] == [[True, True],[False, False]] listbool [[1],[5,5],[5,4],[2]] == [[True],[False, False],[True, True], [False]]
So always True from the elements of the first list, False from the elements of the second one, etc...
Sure you can do this. In fact, the type can be more general:
listbool :: [[a]] -> [[Bool]] listbool xs = zipWith ($) (map (\x -> map (const x)) (cycle [True, False])) xs
Cheers, Edward _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe