PyParsing

I just bought and read the Getting Started with Pyparsing PDF book. And it’s good. PyParsing is a way of building a parser using Python code. You should think Yacc/Lex, but readable. It can be used to parse text, and it can also handle HTML.

This is the example from the PyParsing website :

from pyparsing import Word, alphas
greet = Word( alphas ) + "," + Word( alphas ) + "!" # <-- grammar defined here
hello = "Hello, World!"
print hello, "->", greet.parseString( hello )

OnLamp.com had a good article called Building Recursive Descent Parsers with Python, which is a good starting point. But the book is better.