-lines breaks a string up into a list of strings at newline characters.
-The resulting strings do not contain newlines. Similary, words
-breaks a string up into a list of words, which were delimited by
-white space. unlines and unwords are the inverse operations.
-unlines joins lines with terminating newlines, and unwords joins
-words with separating spaces.
-
-\begin{code}
-lines :: String -> [String]
-lines "" = []
-lines s = let (l, s') = break (== '\n') s
- in l : case s' of
- [] -> []
- (_:s'') -> lines s''
-
-words :: String -> [String]
-words s = case dropWhile {-partain:Char.-}isSpace s of
- "" -> []
- s' -> w : words s''
- where (w, s'') =
- break {-partain:Char.-}isSpace s'
-
-unlines :: [String] -> String
-#ifdef USE_REPORT_PRELUDE
-unlines = concatMap (++ "\n")
-#else
--- HBC version (stolen)
--- here's a more efficient version
-unlines [] = []
-unlines (l:ls) = l ++ '\n' : unlines ls
-
-#endif
-
-unwords :: [String] -> String
-#ifdef USE_REPORT_PRELUDE
-unwords [] = ""
-unwords ws = foldr1 (\w s -> w ++ ' ':s) ws
-#else
--- HBC version (stolen)
--- here's a more efficient version
-unwords [] = ""
-unwords [w] = w
-unwords (w:ws) = w ++ ' ' : unwords ws
-#endif
-
-\end{code}
-