docs: def p_encaps_list(p):
      '''encaps_list : encaps_list encaps_var
                     | empty'''
      if len(p) == 3:
          if p[1] == '':
              p[0] = p[2]
          else:
              p[0] = ast.BinaryOp('.', p[1], p[2], lineno=p.lineno(2))
      else:
          p[0] = ''