[pcwalton]

Rust can.

[tuxychandru]

Are you referring to compiler plugins like the one providing regex! macro or is it something else?

[wycats]

Yes, compiler plugins. For a relevant example, check out the Rust docopt crate[1].

An identical technique could be used for yacc or protobufs.

[1]: https://github.com/docopt/docopt.rs