writeFilename :: Parser InputLine
writeFilename = do
  char 'w'
  many1 (char ' ')
  filename <- many1 (notChar ' ')
  return (WriteFilename filename)
writeFilename :: Parser InputLine
writeFilename = do
  char 'w'
  many1 (char ' ')
  filename <- many1 (notChar ' ')
  return (WriteFilename filename)
writeFilename = do
  char 'w'
  many1 (char ' ')
  filename <- many1 (notChar ' ')
  return (WriteFilename filename)