all tasks

Task/Substring-Top-and-tail/Haskell/substring-top-and-tail.hs

@@ -0,0 +1,18 @@
+-- We define the functions to return an empty string if the argument is too
+-- short for the particular operation.
+
+remFirst, remLast, remBoth :: String -> String
+
+remFirst "" = ""
+remFirst cs = tail cs
+
+remLast "" = ""
+remLast cs = init cs
+
+remBoth (c:cs) = remLast cs
+remBoth  _     = ""
+
+main :: IO ()
+main = do
+  let s = "Some string."
+  mapM_ (\f -> putStrLn . f $ s) [remFirst, remLast, remBoth]