# Need help for regular expression

**URL:** <https://www.ruby-forum.com/t/need-help-for-regular-expression/142051>\
**Category:** Ruby\
**Created:** [July 2, 2008, 11:49pm UTC](https://www.ruby-forum.com/t/need-help-for-regular-expression/142051 "2008-07-02T23:49:52Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![alex-osu3](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/13edae/32.png) [@alex-osu3](https://www.ruby-forum.com/u/alex-osu3)\
**Post date:** [July 2, 2008, 11:49pm UTC](https://www.ruby-forum.com/t/need-help-for-regular-expression/142051/1 "2008-07-02T23:49:52Z")

</div>

Hi all,

I wonder what is the regular expression for this line. What I try to do  
is to remove “(some text here)” from a long string.

Thanks,

Li

string=…(some text here)…

---

<div class="post-metadata">

**Author:** ![alex-osu3](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/13edae/32.png) [@alex-osu3](https://www.ruby-forum.com/u/alex-osu3)\
**Post date:** [July 3, 2008, 1:06am UTC](https://www.ruby-forum.com/t/need-help-for-regular-expression/142051/2 "2008-07-03T01:06:01Z")

</div>

On Jul 2, 5:46 pm, Li Chen [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote:

> –  
> Posted viahttp://www.ruby-forum.com/.

This works.

“…(some text here)…”.sub(‘(some text here)’,‘’)

---

<div class="post-metadata">

**Author:** ![alex-osu3](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/13edae/32.png) [@alex-osu3](https://www.ruby-forum.com/u/alex-osu3)\
**Post date:** [July 3, 2008, 1:06am UTC](https://www.ruby-forum.com/t/need-help-for-regular-expression/142051/3 "2008-07-03T01:06:36Z")

</div>

On Jul 2, 3:46 pm, Li Chen [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote:

> –  
> Posted viahttp://www.ruby-forum.com/.

Li,

Well, there are few different ways.

string.sub!(/(._?)/,‘’)  
string.sub!(/([^)]_)/,‘’)

If there’s a chance that there will be nested parentheses, you’ll need  
something more complicated.

It seems like you’re often asking regular expression questions. I’d  
highly recommend picking up Mastering Regular Expressions by Jeffrey  
Friedl. After reading just the first two chapters, you’ll be able to  
figure stuff like this out very easily. After reading a few more  
chapters, you’ll know the difference between the two expressions above  
and which one you want to use.

HTH,  
Chris

---

<div class="post-metadata">

**Author:** ![alex-osu3](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/13edae/32.png) [@alex-osu3](https://www.ruby-forum.com/u/alex-osu3)\
**Post date:** [July 3, 2008, 1:20am UTC](https://www.ruby-forum.com/t/need-help-for-regular-expression/142051/4 "2008-07-03T01:20:48Z")

</div>

Chris S. wrote:

> On Jul 2, 3:46?pm, Li Chen [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote:
> 
> > –  
> > Posted viahttp://www.ruby-forum.com/.
> 
> Li,
> 
> Well, there are few different ways.
> 
> string.sub!(/(._?)/,‘’)  
> string.sub!(/([^)]_)/,‘’)
> 
> If there’s a chance that there will be nested parentheses, you’ll need  
> something more complicated.
> 
> It seems like you’re often asking regular expression questions. I’d  
> highly recommend picking up Mastering Regular Expressions by Jeffrey  
> Friedl. After reading just the first two chapters, you’ll be able to  
> figure stuff like this out very easily. After reading a few more  
> chapters, you’ll know the difference between the two expressions above  
> and which one you want to use.
> 
> HTH,  
> Chris

Hi Chris,

Thank you very much. I will take a look at “Mastering Regular  
Expressions”.

Li