RosettaCodeData/Task/Word-wrap/Haskell/word-wrap-1.hs

26 lines
1.0 KiB
Haskell

ss =
concat
[ "In olden times when wishing still helped one, there lived a king"
, "whose daughters were all beautiful, but the youngest was so beautiful"
, "that the sun itself, which has seen so much, was astonished whenever"
, "it shone in her face. Close by the king's castle lay a great dark"
, "forest, and under an old lime-tree in the forest was a well, and when"
, "the day was very warm, the king's child went out into the forest and"
, "sat down by the side of the cool fountain, and when she was bored she"
, "took a golden ball, and threw it up on high and caught it, and this"
, "ball was her favorite plaything."
]
wordwrap maxlen = wrap_ 0 . words
where
wrap_ _ [] = "\n"
wrap_ pos (w:ws)
-- at line start: put down the word no matter what
| pos == 0 = w ++ wrap_ (pos + lw) ws
| pos + lw + 1 > maxlen = '\n' : wrap_ 0 (w : ws)
| otherwise = ' ' : w ++ wrap_ (pos + lw + 1) ws
where
lw = length w
main = mapM_ putStr [wordwrap 72 ss, "\n", wordwrap 32 ss]