Changing [[Prototype]]

Brendan Eich brendan at
Fri Dec 28 12:33:14 PST 2012

Rick Waldron wrote:
> In the past I've engaged members of the node community about this and 
> general response is: "______ didn't know about the ES5 APIs".
> ...which is certainly not a reason to include them in any part of the 
> specification, annex or not

Right. So the full answer to Andreas and others' query about why 
__proto__ normative mandatory in ES6 but no __define/lookup... is

1. __proto__ much more used on the mobile (iOS WebKit-first) web, no 
equivalent interop pressure for __d/l.

2. ES5 is in all new/evergreened browsers and it has standard APIs 
supplanting __d/l but nothing for writing to __proto__.

Therefore __proto__ gets standardized, __d/l do not. And I'm done typing 


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