Save Object.observe()! (please) + make WeakMap/WeakSet observable.

Isiah Meadows isiahmeadows at
Wed Nov 4 03:33:00 UTC 2015

There's a reason Object.observe is async: it prevents you from changing how
the value is first assigned, so it can't work like a proxy. And question:
how does it let you see hidden closures?

On Tue, Nov 3, 2015, 18:28 Coroutines <coroutines at> wrote:

> On Tue, Nov 3, 2015 at 3:22 PM, Coroutines <coroutines at> wrote:
> > But because of what Object.observe() can do to see into closures, I'd
> > relegate it to privileged code :>  It is incredibly useful for
> > debugging.
> I really need to make sure my thoughts are complete before I send a
> message.
> Anyway, I just wanted to say I'm viewing this through my experience with
> Lua.
> In Lua you would make a proxy (like I mentioned before) by creating an
> empty table and setting the __index and __newindex metamethods to
> trigger when a key doesn't exist for an access or having its value
> set.  This is the only way to watch for changes, you cannot attach a
> watch to an existing object - you create a separate object to act as
> the proxy and replace the references to the existing/target object.
> My last message was me realizing that Object.observe() has
> functionality that would let you see into encapsulated, hidden
> closures.  This is why I think Object.observe() is cool but probably
> shouldn't be web-accessible.
> Proxy is safe, Object.observe() should be debug-only functionality
> ((imo)).  Like, in browsers you'd only have access to it from the
> console not from within a page?
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