package simbolos1 is
  type claseSimbolo is (esOperando,esOperador,final);
  type simbolo (clase:claseSimbolo:=final) is
	record
	  case clase is
	  	when esOperando => elOperando:integer;
		when esOperador => elOperador:character;
		when final => null;
	  end case;
	end record;
  function operar (o1,o2:in integer; op:in character) return integer;
  procedure siguienteSimbolo (s:in out simbolo);
end simbolos1;