Function identity of non-configurable accessors

Mark S. Miller erights at
Tue Dec 18 10:49:03 PST 2012

On Tue, Dec 18, 2012 at 10:23 AM, Allen Wirfs-Brock
<allen at> wrote:
> If we are only talking about the Global Object, we can probably accommodate
> almost anything by defining it as a special kind of exotic object.

AFAICT, we are only talking about the global object, in order to deal
with the navigation behavior embodied by WindowProxy.

> We
> already have special case handling for declarations and identifier
> resolution involving it.  But once we're in the space of arbitrary exotic
> objects I think we should be very careful about trying to identify and
> enforce additional invariants.

By "invariant" here, I only mean those that are universal. NONE of the
invariants we have been discussing here have applied only to ordinary
objects. We are not talking about adding any additional invariants.
But we should certainly flesh out the list of invariants we've got so
they form a coherent set. The getter/setter-identity issue is the only
such that I've seen in this thread which we had previously failed to
identify, though no doubt there are others. But this doesn't seem to
be the invariant you're arguing with. The more general
"non-configurable implies stability" invariant isn't new, and has
always applied to exotics.


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