class A {
say() {
console.log('i am A');
}
}
const a1 = new A();
const a2 = new A();
console.log(a1.__proto__.say); // f say()
console.log(a1.say === a2.say); // true
class B {
say = function() {
console.log('i am B');
}
}
const b1 = new B();
const b2 = new B();
console.log(b1.__proto__.say); // undefined
console.log(b1.say === b2.say); // false
原来,换种写法就上不了原型链了。
babel 结果:Babel · The compiler for writing next generation JavaScript