Update: The Rspec conversion is done, and I added a section demonstrating macro methods. Read the latest here.
Early last year I published A Ruby Metaprogramming Introduction on the Practical Ruby blog. Earlier this year while commuting back and forth between Grand Central and White Plains—not a place you should strive to commute to, though MetroNorth is far better than the subway for giving you room to work on a laptop—I started making refinements and converting it to use Rspec instead of custom Test::Unit extensions.
I put it aside for a while but am now resolved to continue work on it. I've just put that work onto Github, so anyone with an interest can take a look, browse history, and even submit suggested patches.
The project is located here:
If you're annoyed at the half-Rspec state of things, you can read the originally published version in this tree. (It's way prettier as rendered on Github than I could probably manage to get it on any blog.)