Cross-frame symbols

Brendan Eich brendan at
Fri Oct 12 10:27:06 PDT 2012

Alex Russell wrote:
> It's unclear how we could possibly do this for anything but built-ins, 
> and even there it's iffy. What if someone extends you builtin's 
> prototype in one frame but not the other?
> Anyhow, this all bottoms out at object identity. Functions are 
> objects, and declaring identically named objects in different 
> scripting contexts doesn't make the same object. To get there, you 
> need some iron-clad notion of "sameness". Inventing it is fraught. My 
> recommendation is to use frames a chunky barriers through which you do 
> IPC, not fine-grained object boundaries over which you call local methods.


If you *do* make a "small world network" of objects that span frame 
boundaries, then you're generally keeping it "all in the family" and can 
cope via copying, adding instanceOf or typeOf methods, etc.


> On Fri, Oct 12, 2012 at 5:21 PM, Axel Rauschmayer <axel at 
> <mailto:axel at>> wrote:
>     I’m not sure that I don’t understand all the issues involved, but
>     making symbols global just for cross-frame communication seems
>     like an extreme measure. If that is possible, it would be great if
>     we could fix cross-frame communication completely – also for
>     instanceof, not just for symbols.
>     Does it make sense to view this as a serialization problem? One
>     faces the same problem as in sending an object over a wire: If you
>     create new Foo() at one end, you want that object to be instanceof
>     Foo at the other end.
>     Axel
>     -- 
>     Dr. Axel Rauschmayer
>     axel at <mailto:axel at>
>     home: <>
>     twitter: <>
>     blog: <>
>     _______________________________________________
>     es-discuss mailing list
>     es-discuss at <mailto:es-discuss at>
> _______________________________________________
> es-discuss mailing list
> es-discuss at

More information about the es-discuss mailing list