`super` and superclass constructor return values

[Logan Smyth]

Yup, correct. The value of the `this` binding is initialized to the result
of `[[Construct]]`, which will either be the parent constructor `this`
binding, or the explicitly returned value.

Relevant spec links:
Evaluating `super()`: (12.3.5.1)
http://www.ecma-international.org/ecma-262/6.0/#sec-super-keyword-runtime-semantics-evaluation
Returning a value from a constructor: (9.2.2 step 13.b)
http://www.ecma-international.org/ecma-262/6.0/#sec-ecmascript-function-objects-construct-argumentslist-newtarget


On Fri, Oct 16, 2015 at 2:24 PM, Eric Faust <efaust at mozilla.com> wrote:

> Hi Isiah,
>
> My understanding is that this should log "true". Class constructors may
> return any object they wish, and needn't return instances of the class.
>
> Hopefully, this will allow you to simplify.
>
> Thanks,
>
> Eric
>
> On Fri, Oct 16, 2015 at 2:02 PM, Isiah Meadows <isiahmeadows at gmail.com>
> wrote:
>
>> What should `this` be in class `B`? The value of `object` or an instance
>> of `B`? It's an edge case, but could simplify my code a little if it's the
>> former.
>>
>> ```js
>> const object = {}
>>
>> class A {
>>   constructor() {
>>     return object
>>   }
>> }
>>
>> class B extends A {
>>   constructor() {
>>     super()
>>     console.log(this === object)
>>   }
>> }
>> ```
>>
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>>
>
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