JavaScript的构造函数返回函数并保持继承？ [英] Can JavaScript constructor return function and keep inheritance?

问题描述

function F() {
    return function() {
        return {};
    }
}

var f = new F();
f instanceof F; // returns false

据我所知，如果我想要 instanceof 工作，我需要从构造函数中返回 this 。但我想让构造函数返回一个函数，我不能分配 this 。

As far as I understand, if I want instanceof to work, I need to return this from the constructor. But I want the constructor to return a function, and I cannot assign to this.

不可能或可以以某种方式完成， f = new F（）返回一个函数，然后 f instanceof F 返回true？

So, is this really impossible or can it be done somehow, for f = new F() to return a function and still f instanceof F to return true?

推荐答案

function F() {
    var r = function() {
        return {};
    };

    r.__proto__ = this.__proto__;
    return r;
}

var f = new F();
f instanceof F;
true
f();
Object

仅适用于 __ proto __

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