Lightproof grammar checker development framework


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Average: 4.3 (9 votes)

grammar, checker, language, proofreading, proofreader, spellcheck, spellchecker, spellchecking, spelling, extension
Post date:
Friday, 24 April, 2009 - 04:27
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Lightproof is a grammar checker development framework. The distribution contains also three grammar checker extensions: en_US, hu_HU (see the Lightproof-hu_HU extension page), ru_RU. Download the package to develop a grammar checker for your language (see doc/manual.txt).


– language-neutral proofreading tool (see data/ for language data)
– native Options support
– high-level regex-based rule definition language
– optional Python conditions in the rules
– integration with Hunspell morphological analyser
– written in Python using fast regex module of CPython
– lazy loading of language modules
– template (data/template.dat) for new languages
– optional [code] sections in the rule files to add new Python functions

Lightproof grammar checker development framework

Version Operating system Compatibility Release date
1.4.1 System Independent -- 16/07/2011 - 08:56 More information Download
1.4 System Independent -- 19/02/2010 - 07:55 More information Download
1.3 System Independent 3.4 16/12/2009 - 05:32 More information Download
1.2.2 System Independent 3.0, 3.1, 3.2, 3.3, 3.4 23/10/2009 - 10:46 More information Download
1.2.1 System Independent 3.0, 3.1, 3.2, 3.3, 3.4 20/10/2009 - 04:11 More information Download
1.2 System Independent 3.0, 3.1, 3.2, 3.3, 3.4 19/10/2009 - 03:32 More information Download
1.1 System Independent 3.0, 3.1, 3.2, 3.3, 3.4 03/09/2009 - 17:31 More information Download
1.0.0 System Independent 3.0, 3.1, 3.2, 3.3, 3.4 24/04/2009 - 21:01 More information Download


Nice work. Can this be changed from a zip file to the proper extension?


Also any updates are greatly appreciated.

Lightproof is a great tool!

Is there a roadmap? Do you still work on it?

By the way, here is few improvements I am willing to backport to Lightproof :
[[ deleted ]]

I have installed Lightproof on OOO3.1.1, restarted OOO entered this text:

"This sentence is a grammar nightmare? There did by no way to sense make of this. Grammar checking are useless is will you get hosed."

and LT did not flag any errors.

As far as I am concerned, LT is worthless, unless someone can point out my error in using LT.

Lightproof is a framework to develop proofreading extensions (checkers working on sentence level). The English demo extension contains some punctuation checking and a few real grammar rules. Lightproof has some interesting feature, for example, native Options dialog support, programmable rules with user defined Python codes, Hunspell integration (over UNO) for spell checking and morphological analysis) etc. Real grammar checking is only one of the possible tasks of a proofreading extension. For example, Settings dialog of the Hungarian extension contains three sections: orthographical, proofreading and typographical options (for example, optional rules for suggesting word forms with Unicode ligatures). In my opinion, punctuation checking is more important for proofreading. (Moreover, I believe, using default ambiguous rule based or statistical grammar checking is a nightmare for the average user because of the false alarms.) [By the way, LT is the acronym of the LanguageTool grammar checker extension (not Lightproof).]


used OO 3.0.1 and lightproof 0.9.4. The installation was sccessful and without problems.
Today i have update the OO to 3.1.0 and wanna update lightproof to 1.0.0 but it fails with an java exceptions... an uninstall fails too.
How can i update or install lightproof 1.0.0 in OO 3.1.0, or remove lightproof 0.9.4 from OO 3.1.0?
Is this a know issue?

many thanks Bob


LanguageTool 0.9.4 and Lightproof 1.0 are different programs. English grammar checking rules of Lightproof are mostly limited
to punctuation checking yet, unlike the LanguageTool grammar checker extension. You can update LanguageTool here:

A possible issue with Lightproof: broken Python–UNO Bridge on Mac OS X (Issue 92661). A fix from MultiRacio:

I have successfully tested Lightproof 1.0 also with OOo 3.1 RC 1, but only on Windows. If you have installation problems, you can remove all extensions by deleting the uno_packages folder, see LanguageTool extension page for the instructions.

Best regards,