Frozen Date objects?

[Brandon Benvie]

On 7/17/2013 1:30 PM, Allen Wirfs-Brock wrote:
> Didn't we discuss making the [[DateValue]] immutable when a Date object is non-extensible?  I see this isn't currently in the ES6 draft.  Also, thinking about it now, that seems like quite a one-off hack.

It also brings up the question of, for example, should freezing a Map 
cause [[MapData]] to be frozen? I think the argument for [[MapData]] and 
[[DateValue]] is the same, either way. Similarly, what about freezing a 
RegExp? Should that not prevent `regexp.compile()`?