The `super` keyword doesn't work as it should?

[Andrea Giammarchi]

`super === Object.getPrototypeOf(this)` also doesn't work with multiple
inheritance.

If interested, it has been solved dynamically in this good'ol library:
https://github.com/WebReflection/es-class#es6-ready

Regards

On Tue, Jul 19, 2016 at 11:03 AM, /#!/JoePea <joe at trusktr.io> wrote:

> Hi Bergi, yes, so the object that `super` references would work like
> `this`, where the value is determined at runtime instead of in a
> declaration. Basically, `super === Object.getPrototypeOf(this)` would
> actually be true in my examples. It may be due to ["extra overhead"](
> http://disq.us/p/1a56gxj) that `[[HomeObject]]` is only defined during
> declaration, but that is at the huge expense of making the language less
> intuitive and also more difficult to work with in some cases (for example,
> in designing a multiple-inheritance scheme).
>
> It would simply be great for super to just work as expected in the
> examples I gave, which would mean that super would work in tandem and
> intuitively with the various ways in which we can create
> objects-extending-objects in JS.
>
> Good news is that making the necessary change to `super` in ES8 or later
> is completely backwards compatible with how it currently works.
>
> I wonder what the performance problems are and if they can be solved.
>
> */#!/*JoePea
>
> On Mon, Jul 18, 2016 at 2:46 PM, Bergi <a.d.bergi at web.de> wrote:
>
>> /#!/JoePea wrote:
>>
>> Why can't `super` simply be a shortcut
>>> for "look up the prototype of the object that the method is called on,
>>> then
>>> find the `.constructor` property and call it on `this`"? That seems to be
>>> simple.
>>>
>>
>> Simple, yes, and broken in the case of multi-level inheritance:
>> ```
>> const x = Object.assign(Object.create({
>>     method() {
>>         console.log("parent");
>>     }
>> }), {
>>     method() {
>>         console.log("child");
>>         Object.getPrototypeOf(this).method(); // super.method()
>>     }
>> });
>> x.method(); // works as expected
>>
>> const y = Object.create(x);
>> y.method(); // infinite loop/stack overflow
>> ```
>> A `super` query must not depend on `this` (only), it must statically
>> resolve the object on which the called method is defined.
>>
>> In constructors, using the prototype of the currenctly called constructor
>> for `super()` works well, but you'd need to use `Object.setPrototype` as
>> there is currently no declarative way other than `class`es to define
>> functions with custom prototypes.
>>
>> In methods, there would need to be a way to populate the [[HomeObject]]
>> other than declaring the method as part of a class/object literal.
>>
>> Kind regards,
>>  Bergi
>> _______________________________________________
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>>
>
>
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