RubyMacros is a lisp-like macro pre-processor for Ruby. More than just a purely textual substitution scheme, RubyMacros can manipulate and morph Ruby parse trees (in the form of RedParse Nodes) at parse time in just about any way you see fit. Macros are programmed in ruby itself. And since parse trees are represented in RedParse format, they're easier to use (programatically) and more object- oriented than other available ruby parsetree formats. (RedParse Node format is actually designed to be straightforward to use and to represent the structure of ruby source code very closely.)