Foundation: NSString init detect encoding

Hey,

I've been looking at the init(contentsOfFile, usedEncoding) initializer for
NSString in corelibs-foundation.

Am I right in thinking that this initializer should use some method to
attempt to detect the character encoding of the file before returning a
decoded String?

If so, I've been working on a pure Swift library to detect string
encodings, and wondered if continued work on it might be useful for
implementing this missing initializer?

Andy