https://github.com/jirikuncar/esmre

Automatically exported from code.google.com/p/esmre
https://github.com/jirikuncar/esmre

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Automatically exported from code.google.com/p/esmre

• Host: GitHub
• URL: https://github.com/jirikuncar/esmre
• Owner: jirikuncar
• License: lgpl-2.1
• Created: 2015-06-25T12:57:00.000Z (over 9 years ago)
• Default Branch: master
• Last Pushed: 2015-07-12T18:32:49.000Z (over 9 years ago)
• Last Synced: 2024-10-31T10:02:09.814Z (2 months ago)
• Language: C
• Size: 242 KB
• Stars: 1
• Watchers: 3
• Forks: 1
• Open Issues: 6
• Metadata Files:
  • Readme: README
  • License: COPYING

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README

        
esmre - Efficient String Matching Regular Expressions

=====================================================

esmre is a Python module that can be used to speed up the execution of a large

collection of regular expressions. It works by building a index of compulsory

substrings from a collection of regular expressions, which it uses to quickly

exclude those expressions which trivially do not match each input.

Here is some example code that uses esmre:

>>> import esmre

>>> index = esmre.Index()

>>> index.enter(r"Major-General\W*$", "savoy opera")

>>> index.enter(r"\bway\W+haye?\b", "sea shanty")

>>> index.query("I am the very model of a modern Major-General.")

['savoy opera']

>>> index.query("Way, hay up she rises,")

['sea shanty']

>>> 

The esmre module builds on the simpler string matching facilities of the esm

module, which wraps a C implementation some of the algorithms described in

Aho's and Corasick's paper on efficient string matching [Aho, A.V, and

Corasick, M. J. Efficient String Matching: An Aid to Bibliographic Search.

Comm. ACM 18:6 (June 1975), 333-340]. Some minor modifications have been made

to the algorithms in the paper and one algorithm is missing (for now), but

there is enough to implement a quick string matching index.

Here is some example code that uses esm directly:

>>> import esm

>>> index = esm.Index()

>>> index.enter("he")

>>> index.enter("she")

>>> index.enter("his")

>>> index.enter("hers")

>>> index.fix()

>>> index.query("this here is history")

[((1, 4), 'his'), ((5, 7), 'he'), ((13, 16), 'his')]

>>> index.query("Those are his sheep!")

[((10, 13), 'his'), ((14, 17), 'she'), ((15, 17), 'he')]

>>> 

You can see more usage examples in the tests.