[Hugs-users] converting to capital letters

Hi, I am a newbie in Haskell and have some problem of defining a function that would convert all small letters to capital and leave the rest intact. I have managed to do with two functions: capitalise :: String -> String capitalise xs = [capitalise2 ch| ch<-xs] capitalise2 :: Char -> Char capitalise2 ch | isLower ch = chr (ord ch - 32) | otherwise = ch But in the book exercise it asks to define as a single function. I tried like this: capitalise :: String -> String capitalise xs = [chr (ord ch - 32) | ch<-xs, isLower ch] But this returns only converted characters, the rest is ignored. Any help would be much appriciated. Send instant messages to your online friends http://uk.messenger.yahoo.com