Other examples of things one can do with metaprogramming: async/await http://nim-lang.org/docs/asyncdispatch.html#async , pattern matching http://andreaferretti.github.io/patty/ , for/do comprehensions https://github.com/vegansk/nimfp/blob/master/tests/fp/test_f...
... define decorator-like Nim pragmas that generate Python C-API boilerplate code for decorated Nim procs, to auto-generate type-safe, exception-safe, refcount-safe Python bindings for Nim? https://github.com/jboy/nim-pymod :)