# Regular Expressions

**URL:** https://community.mp3tag.de/t/regular-expressions/521
**Category:** Howto
**Created:** [October 16, 2003, 4:47pm UTC](https://community.mp3tag.de/t/regular-expressions/521 "2003-10-16T16:47:29Z")
**Posts on this page:** 1
**Showing post:** 52

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### Author: ![dano](https://community.mp3tag.de/user_avatar/community.mp3tag.de/dano/32/6_2.png) [@dano](https://community.mp3tag.de/u/dano)
#### Post date: [April 5, 2013, 10:39am UTC](https://community.mp3tag.de/t/regular-expressions/521/52 "2013-04-05T10:39:03Z")

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It's not a bug.  
It happens because global matching is activated by default.  
That means the engine tries to match the regex pattern as many times as possible.

With (._) the whole text is matched at first. Then the engine stands at the end of the text. And it tries to match the pattern again.  
And it succeeds because ._ also matches "nothing".

But I'd prefer a simple "Format value" action is for this task anyway.

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