_racc_do_reduce

# File lib/racc/parser.rb, line 472
    def _racc_do_reduce(arg, act)
      _, _, _, _,
      goto_table,   goto_check,   goto_default,   goto_pointer,
      nt_base,      reduce_table, _,    _,
      _,     use_result,   * = arg
      state = @racc_state
      vstack = @racc_vstack
      tstack = @racc_tstack

      i = act * -3
      len       = reduce_table[i]
      reduce_to = reduce_table[i+1]
      method_id = reduce_table[i+2]
      void_array = []

      tmp_t = tstack[-len, len] if @yydebug
      tmp_v = vstack[-len, len]
      tstack[-len, len] = void_array if @yydebug
      vstack[-len, len] = void_array
      state[-len, len]  = void_array

      # tstack must be updated AFTER method call
      if use_result
        vstack.push __send__(method_id, tmp_v, vstack, tmp_v[0])
      else
        vstack.push __send__(method_id, tmp_v, vstack)
      end
      tstack.push reduce_to

      racc_reduce(tmp_t, reduce_to, tstack, vstack) if @yydebug

      k1 = reduce_to - nt_base
      if i = goto_pointer[k1]
        i += state[-1]
        if i >= 0 and (curstate = goto_table[i]) and goto_check[i] == k1
          return curstate
        end
      end
      goto_default[k1]
    end