Does private(expr) create a private storage block?

Herby Vojčík herby at
Fri Jan 20 02:42:00 PST 2012

Sorry, misunderstood the question.

Andrea Giammarchi wrote:
> On Fri, Jan 20, 2012 at 2:24 AM, Herby Vojčík <herby at
> <mailto:herby at>> wrote:
>     Let the object created is foo. When calling foo.method(), it is
>     accessing private(foo), not private(objectWithPrivates), since this
>     is foo. "If yes" does not happen. Errors may happen since foo
>     probably does not have private space (my proposal in this thread is
>     touching this issue).

> 2. what if Object.create(objectWithPrivates, descriptor) ? would
> descriptor methods be able to invoke objectWithPrivates.method()
> with private(this) access in the function body? If yes, would that
> private(this) refer to the objectWithPrivates? This would violate
> the objectWithPrivates private concept, isn't it?

> Object.create accept the __proto__ and a descriptor, I am not sure a
>  descriptor will/should ever have a private(this) configured unless
> there is not a class for the descriptor but the list of
> configurations won't make much sense, i.e.
> {value: function () { this instanceof OuterClass /* not possible, it's
> just an object */ }}

It is an error to use private keyword outside the class block. So, no 
extension with private(this) using methods at all outside it.
If aforementioned Object.create would appear inside class block, then 
according to actual state of the proposal, as I understand it, it is an 
error to use private keyword, too. It can only be used in methods (and 
constructor). But with I am less sure.
My proposal is to make use of private keyword much more liberated, in 
that case if your Object.create would appear inside (any) class block, 
it would work and added (that class's whose the class block is) private 
access, outside class block it would not.


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