index.js
function Foo() {}
const foo = new Foo();
console.log(foo instanceof Foo); // true
// 等价于
console.log(Foo.prototype.isPrototypeOf(foo)); // true
index.js
function Foo() {}
const foo = new Foo();
console.log(foo instanceof Foo); // true
// 等价于
console.log(Foo.prototype.isPrototypeOf(foo)); // true