Haskell 練習

practice.hs

madam = "Madam, I'm Adam."

remove chr str = [c | c <- str, c /= chr]
removeCommas  str = remove ',' str
removeBlanks  str = remove ' ' str
removePeriods str = remove '.' str
{--
removeCommas  str = [c | c <- str, c /= ',']
removeBlanks  str = [c | c <- str, c /= ' ']
removePeriods str = [c | c <- str, c /= '.']
--}
removeBPC str = ((removeCommas.removeBlanks.removePeriods) str)
removeAd str = (remove 'A'. remove 'd') str

main = do
  print $ madam
  print (removeCommas(madam))
  print (removeBPC madam)
  print $ remove '\'' madam
  print $ removeAd madam

--- Output
{--
"Madam, I'm Adam."
"Madam I'm Adam."
"MadamI'mAdam"
"Madam, Im Adam."
"Maam, I'm am."

--}