gistfile1.hs

{- learning from http://learnyouahaskell.com/ -}
doubleMe x = x + x
doubleSmall x = if x > 100
                  then x
                  else x * 2
len xs = sum [1 | _ <- xs]
per = ("Paulo", 28)
removeNonUppercase :: [Char] -> [Char]
removeNonUppercase st = [c | c <- st, elem c ['A'..'Z']]

pm 7 = "I'm a Seven"
pm _ = "You have not typed a Seven :("

replicate' :: (Num i, Ord i) => i -> a -> [a]
replicate' n x
    | n <= 0 = []
    | otherwise = x:replicate' (n-1) x

take' :: (Num i, Ord i) => i -> a -> [a]
take' n _ 
    | n <= 0 = []
take' _  [] = []
take' n (c:xs) = c : take' (n-1) xs
    
reverse' :: (Ord i) => [i] -> [i]
reverse' [] = []
reverse' (x:xs) = reverse' xs ++ [x]