Reflection of global bindings

Boris Zbarsky bzbarsky at MIT.EDU
Sat Dec 15 10:02:07 PST 2012


On 12/15/12 12:48 PM, David Bruant wrote:
>> Sure, but those aren't properties on the _global_.  They're properties
>> on a different object.
> Script authors can't observe the fact that it's a different object.

Yes, they can.  The third and fourth alerts in my testcase constitute 
just such an observation: per spec the third alert there must be looking 
at a property of the global, and it is, while the fourth alert is 
clearly looking at some other object, since it has a different value for 
the property.

There's a slight wrench in here in that the script-visible "this" object 
for non-strict functions is also supposed to be the global per spec, but 
in practice it's the WindowProxy.

> They just have access to one WindowProxy object (they know it's the same with
> object identity).

They have direct access to just the WindowProxy.  They have access to 
property gets and sets on the actual global, though, via barewords.

> This object is the one that must show some consistency.

That, we agree on.

-Boris


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