If the NSError part of the box hasn't been initialized yet, fill it in with the domain and code of the contained value. This will allow us to efficiently turn ErrorType values into NSErrors, either for bridging or for coercion purposes.
Swift SVN r26958
This allows ErrorTypes referencing Cocoa NSErrors to be pattern-matched against our bridged enums, at least dynamically. (The compiler still doesn't understand these bridging conversions yet.)
Swift SVN r26839
After some more discussion with John, we decided that subclassing is the only realistic option, at least until we eventually are able to integrate with the OS. Switch things around to allocate Swift error boxes as an ObjC subclass that contains the error value instead of trying to game it as a CFError.
Swift SVN r26562
Teach ExistentialTypeMetadata how to project out the value pointer, type metadata, and protocol witness table from ErrorType containers. NFC yet; the dynamic casting and reflection machinery needs further work to correctly handle ErrorType boxes.
Swift SVN r26509
