The team behind Scala is adding an experimental version of macros in the forthcoming release version 2.10. Scala macros provide an advanced form of compile-time meta-programming.
As of version 11, macros will no longer be available in Visual Studio. This marks the first version in nearly a decade to not allow for crating ad-hock extensions to the IDE. Fully compiled extensions can still be created and new project templates are included to make that process much easier.