Introduction

pyahocorasick is a Python module implements two kinds of data structures: trie and Aho-Corasick string matching automaton.

Trie is a dictionary indexed by strings, which allow to retrieve associated items in a time proportional to string length. Aho-Corasick automaton allows to find all occurrences of strings from given set in a single run over text.

(BTW in order to use Aho-Corasick automaton, a trie have to be created; this is the reason why these two distinct entities exist in a single module.)

There are two versions:

• C extension, compatible only with Python3;
• pure python module, compatible with Python 2 and 3.

Documentation

Documentation of C extension API is available on separate page.

Python module API is similar, but isn't exactly the same.

Last changes

2011-04-13

• select support for either unicode or bytes
• simple pattern matching

License

Library is licensed under very liberal two-clauses BSD license. Some portions has been released into public domain.

Full text of license is available in LICENSE file.

Downloads

Following files are available:

• C extension sources — pyahocorasick.tgz [2011-04-14]
• Python module — pyahocorasick.py

See also

• Module ahocorasick by Danny Yoo — seems unmaintained (last update in 2005) and is licensed under GPL.
• Module PyDAWG.
• Article about different trie representations — this is an effect of experiments I made while working on this module.