LGBI.
@codebrainz raised concerns on IRC about having "imperfect" filetype (no symbols and related features like autocompletion and calltips) in core and that people would complain it's broken. I don't really know how used Swift is, and I don't really think it's bets not to have support for a language than having partial one. Opinions? @elextr
BTW, I started a CTags parser for this, but I won't likely have it ready too quickly. But @codebrainz suggested maybe someone could quickly write a regex-based parser based off some ctags command line. Should be fairly easy I think.