Not Available in Obj-C Generics Tuples Enumerations Structures Top-level functions Global variables Typealiases Swift-style variadics Nested types Curried functions
… and much more Standard library WillSet / DidSet in setters Memory management in closures Convenience initializers Lazy properties Nesting of classes, enums and structs Pattern matching in `switch` statements reStructuredText documentation headers Default parameter values in functions Monads, futures, promises and other functional programming constructions Nested comments
Lack of “const correctness” / not completely functional Almost no docs about the standard library Lack of extensive dynamic type information Changes every week (well, almost.)