There is the "flip" function which changes the order of the first 2 parameters Prelude> :t flip flip :: forall c a b. (a -> b -> c) -> b -> a -> c So I think map ( (flip foo) 5 ) my_list_of_lists_of_doubles will work, as will using a lambda expression map (\x -> foo x 5) may_list_of_lists_of_doubles André Vargas Abs da Cruz wrote:
Hi,
I have been using Haskell for a few weeks now and I can say that I am totally impressed by how easy it is to program with it. I am now doing some small exercises to get used to the language syntax and I have a little (newbie) question:
Suppose I declare a function foo like:
foo :: [Double] -> Int -> Int foo a b
Suppose now that I want to apply this function to a list that contains lists of doubles (something like [[Double]]) using map, but I want to keep the 'b' parameter fixed (with a value of 5 for instance). Is it possible to use map passing the function foo with the 2nd argument only ? In other words, if I wrote this function like:
foo :: Int -> [Double] -> Int
I could clearly call it with:
map (foo 5) my_list_of_lists_of_doubles
But how to do that (if possible) when I invert the parameters list ?!
Thanks in advance, Andre Abs da Cruz _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe