rotateRParser :: Parser Instruction
rotateRParser =  string "rotate right " *> (RotateR <$> int <* (string "step" <* skipOptional (char 's')))
rotateRParser :: Parser Instruction
rotateRParser =  string "rotate right " *> (RotateR <$> int <* (string "step" <* skipOptional (char 's')))
rotateRParser =  string "rotate right " *> (RotateR <$> int <* (string "step" <* skipOptional (char 's')))