code: def before_constant(self, constant, key):
          
          newlines_split = split_on_newlines(constant)
  
          for c in newlines_split:
              if is_newline(c):
                  self.current.advance_line()
                  # if target line is passed
                  if self.current.line > self.target.line:
                      return self.STOP
  
              else:
                  advance_by = len(c)
                  if self.is_on_targetted_node(advance_by):
                      self.found_path = deepcopy(self.current_path)
                      return self.STOP
                  self.current.advance_columns(advance_by)
docs: Determine if we're on the targetted node.
  
          If the targetted column is reached, `stop` and `path_found` are
          set. If the targetted line is passed, only `stop` is set. This
          prevents unnecessary tree travelling when the targetted column
          is out of bounds.