Note: typedef is implemented. extend is not.

typedef

To create a named alias for some type, use typedef in the appropriate module's global scope (it may not be placed anywhere else):

typedef Noderef &rc mut Node

In this example, wherever Noderef is used in this module, it will be understood to mean &rc mut Node.

extend

It is possible to enrich an existing type by adding additional methods to it.

extend f32:
  fn cos(self f32) { ... }