[[Extensible]]and Proxies (Was: Proxy.isProxy )

Allen Wirfs-Brock allen at wirfs-brock.com
Thu Jul 14 20:53:42 PDT 2011


On Jul 14, 2011, at 4:59 PM, Mark S. Miller wrote:

> On Thu, Jul 14, 2011 at 3:00 PM, Allen Wirfs-Brock <allen at wirfs-brock.com> wrote:
> 
> 
>> 
> 
> Implementations are free to add new built-in objects (see 4.3.28).  Without any stated requirements for such objects you have no guarantees. 
> 
> Quoting that section in full:
> 
> 4.3.28 
> built-in method 
> method that is a built-in function 
> NOTE Standard built-in methods are defined in this specification, and an ECMAScript implementation may specify 
> and provide other additional built-in methods.  
> 
> My interpretation of this is simply that implementations can provide new built-in methods that are still constrained to operate as native functions if they are to be considered native functions. As with the specified built-in native functions, they can have [[Call]] and [[Construct]] methods that are not written in JavaScript. I don't understand what else you are reading into this, unless it's captured by the peek and poke discussion below.

sorry I meant to refer to 4.3.7 Built-in objects which using the term Native Object.

Note that the definition of Native Objects was changed in ES5 in a manner that I now think is inconsistent with web reality in that it now says that the semantics of (all) native objects are defined by the ES specification.  ES3 did not say that.

Allen  
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.mozilla.org/pipermail/es-discuss/attachments/20110714/47ede5bd/attachment.html>


More information about the es-discuss mailing list