Paul Graham particularly wrote some lovely descriptions of how it all works.Meanwhile: <a href="http://writingcoding.blogspot.com/2008/07/stemming-part-8-macros.htmllooks">http://writingcoding.blogspot.com/2008/07/stemming-part-8-macros.htmllooks</a> like the sort of thing I would have liked to read. (I have not read it closely.