Pythologic - Prolog syntax in Python

The "recipe" for Pythologic is given and discussed here:

http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/303057

The discussion is interesting in itself, as it identifies the "wildly unpythonic" and "abusive" "overhaul of the function semantics" involved. One thing I've always liked about Python is the extent to which it supports this kind of metaprogramming. You can, if the mood takes you, quite seriously deform the language's conventional semantics. That isn't necessarily a good thing; but it can be fun sometimes.

David Mertz has written an article on embedding declarative mini-languages in Python, which demonstrates some other techniques.