a new ES6 spec. draft dis available

Allen Wirfs-Brock allen at wirfs-brock.com
Fri Sep 28 08:32:08 PDT 2012

Nothing new in this section in this draft and what is there will eventually get a significant rewrite...

On Sep 27, 2012, at 9:32 PM, Axel Rauschmayer wrote:

> B.3.1,  “The __proto__ pseudo property” will eventually be moved out of the annex, right?
> If I may: I have two questions about this section.
> 1. Quote: “Manipulations of this property as tracked by the Boolean valued primordial internal variable UnderscoreProtoEnabled.”
>     What is a primordial internal variable? That term does not appear anywhere else in the spec.

No doubt the terminology will change, if we still need it.  What it is describing is a per global context  (per "realm") internal variable.

> 2. Quote: “The default initial value of UnderscoreProtoEnabled is true only if this property is initially present on the primordial Object prototype object.”
>     I would have guessed that the variable being true also depends on whether or not Object.prototype is in the prototype chain.

No, in this draft, it is just tracking manipulation of that specific property of Object.prototype.  The inheritance aspects are taken care of in the [[Get]] and [[Put]] internal methods.

But, it's all moot, as this is destined to be completely rewritten.


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