code: def do_move_to(self, element, decl, pseudo):
          
          target = serialize(decl.value).strip()
          step = self.state[self.state['current_step']]
          elem = self.current_target().tree
  
          #  Find if the current node already has a move, and remove it.
          actions = step['actions']
          for pos, action in enumerate(reversed(actions)):
              if action[0] == 'move' and action[1] == elem:
                  target_index = - pos - 1
                  actions[target_index:] = actions[target_index+1:]
                  break
  
          _, valstep = self.lookup('pending', target)
          if not valstep:
              step['pending'][target] = [('move', elem)]
          else:
              self.state[valstep]['pending'][target].append(('move', elem))
docs: Implement move-to declaration.