You need a method that will find the length of a list: length :: [a] -> Int and a method that will applies a function to every element of a list and make a list of the results: map :: (a ->b) -> [a] -> [b] Try and put them together. hth, -deech On 4/10/10, boblettoj wrote:

Hi i want to know if there is any method i can use to count the number of items in each list in a list of lists, eg.

someMethod [[a, b, c], [a], [b, d, e, f]] would return [3, 1, 4]

is there anything that can do this? thanks

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someMethod :: [[a]] -> [Int] someMethod = map length There's a list, haskell-beginners better suited for this kind of question. Alex On Saturday 10 April 2010 18:02:37 boblettoj wrote:

Hi i want to know if there is any method i can use to count the number of items in each list in a list of lists, eg.

someMethod [[a, b, c], [a], [b, d, e, f]] would return [3, 1, 4]

is there anything that can do this? thanks