*.empty Idea

[Boris Zbarsky]

On 4/30/15 3:46 PM, C. Scott Ananian wrote:
> I like the idea of snapshot methods, but they can be implemented in user
> code using subclasses in ES6.

Can they?  You can't create immutable snapshots in user code afaict...

> But that would still have required an explicit test in
> Map.clear/set/delete to ensure that they were operating on an instanceof
> Map and not just on a ReadOnlyMap.

More likely an internal slot check, not an instanceof check.

-Boris