So, this is early yet - but I'm working with NSRegularExpression in a particular app, and I have noticed two things, it's not a particularly swift-y API and there is no reason that it needs to conform to the NS rules like other types as it could be useful anyplace and everyplace.
I would like to have it be bridgeable to NSRegularExpression, much like strings. I haven't started an implementation yet, although I might just for myself anyway, but wanted to take the pulse of people here. This would be additive so I can't imagine it would mess up the ABI.
The upside could be that we could also make it work for anything
StringRepresentable or similar, or even more wild ideas I have not thought of yet.