code: def inc(self, exception=None):  # type: (Optional[ParseError.__class__]) -> bool
          
          try:
              self._idx, self._current = next(self._chars)
  
              return True
          except StopIteration:
              self._idx = len(self)
              self._current = self.EOF
              if exception:
                  raise self.parse_error(exception)
  
              return False
docs: Increments the parser if the end of the input has not been reached.
          Returns whether or not it was able to advance.