[swift-evolution] [Review] SE-0117: Default classes to be non-subclassable publicly

[Jordan Rose]

> On Jul 11, 2016, at 11:16, Goffredo Marocchi <panajev at gmail.com> wrote:
> 
> So either open by default and sealed optionally or sealed by default and no escape hatch?

I think there are two separate decisions in here:

- Open by default or sealed by default?
- If sealed, can the seal be broken by clients?

These decisions aren’t independent ("if sealed is the default, it’s more important for clients to be able to break it, since it might be an accident”, perhaps), but either can be implemented independently.

Jordan