3 Commits

Author	SHA1	Message	Date
Jordan Rose	3fcdfd40e9	Remove the "swift/Basic/Optional.h" header. ... llvm::Optional lives in "llvm/ADT/Optional.h". Like Clang, we can get Optional in the 'swift' namespace by including "swift/Basic/LLVM.h". We're now fully switched over to llvm::Optional! Swift SVN r22477	2014-10-02 18:51:45 +00:00
Jordan Rose	042569a3be	Optional: Replace uses of Nothing with None. ... llvm::Optional (like Swift.Optional!) uses None as its placeholder value, not Nothing. Swift SVN r22476	2014-10-02 18:51:42 +00:00
Devin Coughlin	3749a98763	Record the reason a declaration is potentially unavailable. ... This commit adds tracking of the reason a declaration reference is potentially unavailable to the UnavailableToOptionalExpr AST node and to OverloadChoice. We will use this reason during SILGen to emit the appropriate run-time check and during typechecking to provide more helpful diagnostics. To keep OverloadChoice as small as possible, we encode the reason as an index into a vector of reasons stored in a given instance of ConstraintSystem (this is the same approach that Fix takes). This commit adds Sema/OverloadChoice.cpp (for the parts of OverloadChoice that now rely on ConstraintSystem) and AST/Availability.h (to bring in availability-related structures without TypeRefinementContext). Swift SVN r22377	2014-09-30 01:53:59 +00:00