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re: What is Javascript's `new` keyword doing under the hood? VIEW POST

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re: You are correct -- I'm certainly having difficulty with understanding how to handle the edge case(s). Always learning! Thanks for taking the time t...

If constructor returns

    return {
      doors,
      color
    }

it is a completely different from newObject object reference and after that if new2 returns the result of constructor the newObject would be just lost in the new2 scope.

So it have to be like

function Car(doors, color) {
    this.doors = doors;
    this.color = color;
    this.drive = () => console.log('Vroom!');
    return this // equals to `newObject` ref
}

function new2(constructor, ...constructorArgs) {
    const newObject = {};
    Object.setPrototypeOf(newObject, constructor.prototype);
    return constructor.apply(newObject, constructorArgs); // bind newObject to constructor's `this` reference and call with args
}

Ah okay, I see what you're saying now. I guess part of what I was trying to convey is that the constructor function can in fact return any object. In which case, the new function should just return that object as is.

What you've presented here is a more realistic edge case. I will think about a way to cover it in the article.

Great insights -- thank you.

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