NLTK 1.1 – Computing with Language: Texts and Words by Vsevolod Dyomkin.
From the post:
OK, let’s get started with the NLTK book. Its first chapter tries to impress the reader with how simple it is to accomplish some neat things with texts using it. Actually, the underlying algorithms that allow to achieve these results are mostly quite basic. We’ll discuss them in this post and the code for the first part of the chapter can be found in nltk/ch1-1.lisp.
A continuation of Natural Language Meta Processing with Lisp.
Who knows? You might decide that Lisp is a natural language. 😉