# Install oniguruma "No definition for oregexp\_initialize "

**URL:** <https://rubytalk.org/t/install-oniguruma-no-definition-for-oregexp-initialize/51299>\
**Category:** ruby-talk\
**Created:** [21 January 2009 05:28 UTC](https://rubytalk.org/t/install-oniguruma-no-definition-for-oregexp-initialize/51299 "2009-01-21T05:28:40Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Mike\_Mike](https://avatars.discourse-cdn.com/v4/letter/m/9fc348/32.png) [@Mike\_Mike](https://rubytalk.org/u/Mike_Mike)\
**Post date:** [21 January 2009 05:28 UTC](https://rubytalk.org/t/install-oniguruma-no-definition-for-oregexp-initialize/51299/1 "2009-01-21T05:28:40Z")

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when I run "gem install oniguruma".

get the message "No definition for oregexp\_initialize "

how to initialize oregexp?

> **···**
>
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> Posted via [http://www.ruby-forum.com/](http://www.ruby-forum.com/).

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**Author:** ![Alex\_Fenton2](https://avatars.discourse-cdn.com/v4/letter/a/7ab992/32.png) [@Alex\_Fenton2](https://rubytalk.org/u/Alex_Fenton2)\
**Post date:** [21 January 2009 12:58 UTC](https://rubytalk.org/t/install-oniguruma-no-definition-for-oregexp-initialize/51299/2 "2009-01-21T12:58:31Z")

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Mike Mike wrote:

> when I run "gem install oniguruma".
> 
> get the message "No definition for oregexp\_initialize "
> 
> how to initialize oregexp?

I think this means you need to install the oniguruma C library and its headers. You don't say what platform you're on, so it's hard to be more specific about how to do that.

Alternatively, you could use Ruby 1.9.1 which has oniguruma built-in, as well as other features to make working with encodings easier (one of the main reasons for using Oniguruma previously).

alex