poemLines.hs

-- poemLines.hs

module PoemLines where

firstSen = "Tyger Tyger, burning bright\n"
secondSen = "In the forests of the night\n"
thirdSen = "What immortal hand or eye\n"
fourthSen = "Could frame thy fearful symmetry?"
sentences = firstSen ++ secondSen
  ++ thirdSen ++ fourthSen

--putStrLen sentences -- should print
-- Tyger Tyger, burning bright
-- In the forests of the night
-- What immortal hand or eye
-- Could frame thy fearful symmetry?

mySplit :: String -> Char -> [String]
mySplit "" _ = []
mySplit x c = firstPart : mySplit remaining c
  where firstPart = takeWhile (/=c) x
        remaining = dropWhile (==c) $ dropWhile (/=c) x

-- Implement this
myLines :: String -> [String]
myLines x = mySplit x '\n'

-- What we want 'myLines sentences' to equal
shouldEqual =
  [ "Tyger Tyger, burning bright"
  , "In the forests of the night"
  , "What immortal hand or eye"
  , "Could frame thy fearful symmetry?"
  ]

-- The main function here is a small test
-- to ensure you've written your function
-- correctly.
main :: IO ()
main =
  print $ "Are they equal? "
    ++ show (myLines sentences == shouldEqual)