Re: Exposing constructors of readonly interfaces to web authors

On Sat, Jun 28, 2014 at 6:43 AM, Brendan Eich <brendan@secure.meer.net>
wrote:

> Dirk Schulze wrote:
>
>> DOMQuad is a new interface and indeed part of general layout efforts that
>> give authors more control and information over layout with JS. With the
>> described behavior, a live object is reasonable IMO.
>>
>
> This side of the discussion still seems to be missing the shared getters
> in prototype point, which is important. The (correct, compared to Rik's --
> thanks!) JS you sketched using Object.defineProperty makes getters *per
> instance*, with fresh getter function suites per instance -- and this is
> observable via ES5 introspection APIs. It's also way too costly for
> implementors to tolerate.


Can't we change the code so it always returns the same getters? ie instead
of creating a new {} and getter function, keep a reference of them in the
object and use them in Object.defineProperty. That way the object's
prototype will always have the same getters and it won't be very costly to
implement.