Hi,

I was wondering if anyone could help clarify expected behavior of 
[[GetOwnProperty]] for named properties of the Window object.  (It looks like 
this falls across the HTML5 & WebIDL specs, apologies if this is the wrong 
place to ask).

Per WebIDL’s definition of [Global] 
(http://dev.w3.org/2006/webapi/WebIDL/#Global) the named properties are exposed 
on a named properties object on the prototype chain.
Per section 4.5.5.1 
(http://dev.w3.org/2006/webapi/WebIDL/#named-properties-object) the 
[[GetOwnProperty]] implementation should return a descriptor with writable set 
to false, enumerable and configurable set to true.

Firefox and Chrome both return descriptors from an object on the prototype 
chain per the spec, attributes of the value are configured differently, with 
enumerable set to false, writable and configurable set to true.

There seem to be some compelling reasons to follow Firefox / Chrome (writable 
true seems more congruent with ECMA262 specified [[Put]], unless there is 
another mechanism I’m missing here, enumerable is odd since I don’t think the 
spec says anything about [[GetOwnPropertyNames]]),so I was hoping to better 
understand why the spec requires the behaviour it does (or whether I’m just 
following it incorrectly!)

Many thanks,
Gavin

Reply via email to