'use strict';

class Animal { constructor(name) { this.name = name; } }

class Cat5 extends Animal { constructor(name) { super(name); }

say5() {
    return `Hello, ${this.name}!`
}

}

// 测试: var kitty5 = new Cat5('Kitty'); var doraemon5 = new Cat5('哆啦A梦'); if ((new Cat5('x') instanceof Animal) && kitty5 && kitty5.name === 'Kitty' && kitty5.say5 && typeof kitty5.say5 === 'function' && kitty5.say5() === 'Hello, Kitty!' && kitty5.say5 === doraemon5.say5) { alert('测试通过!'); } else { alert('测试失败!'); }