Re: ISSUE-66: should Documents that aren\'t being presented be required to have a null defaultView?

On Apr 5, 2006, at 5:39 PM, Jonas Sicking wrote:

> Boris Zbarsky wrote:
>> Ian Hickson wrote:
>>>> 3) Forbid any non-presented Document to implement DocumentWindow  
>>>> (seems too
>>>> restrictive).
>>>
>>> I am strongly in favour of 3. If we don't do 3, we're going to  
>>> have to require a whole heck more than 1 -- we're going to have  
>>> to special case every single API that requires a rendering context.
>> What happens when a document goes from "presented" to "non- 
>> presented" or vice versa?
>> And note that even if we disallow such transitions doing what you  
>> propose would require that all document creations know whether the  
>> document is going to be presented.....  This could be a pretty  
>> heavy burden in some cases.
>
> Actually, it already does happen in some cases. If you hold on to a  
> document inside an iframe and then navigate away from the document  
> the document goes from being presented to being non-presented.

Presumably, back/forward cache plus holding onto a document from  
another window could result in the inverse transition. I discussed  
this with Ian on IRC and he agreed (I think) that non-presented  
documents should be allowed (perhaps even required) to implement  
DocumentWindow in a Window UA, and that their attributes should be  
appropriately neutered. So if we elimitate 3 and 2, that only leaves  
1, require defaultView (and probably other attributes like location)  
to be null for documents that implement DocumentWindow but are not  
presented.

BTW the frame thing is a handy portable way to get a non-presented  
document that implements DocumentWindow for testing purposes.

Regards,
Maciej

Received on Thursday, 6 April 2006 22:36:16 UTC