# Brackets Help
**URL:** https://community.mp3tag.de/t/brackets-help/18516
**Category:** Support
**Created:** [December 13, 2016, 7:37am UTC](https://community.mp3tag.de/t/brackets-help/18516 "2016-12-13T07:37:28Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@rufus](https://community.mp3tag.de/u/rufus)
#### Post date: [December 13, 2016, 7:37am UTC](https://community.mp3tag.de/t/brackets-help/18516/1 "2016-12-13T07:37:28Z")
I have a bunch of music MP3 files in a folder. Some of them have their title tag set as, for example:
Back Up [Feat. xx] [Album Version]
I want to create an action that will define, if title tag has two pairs of square brackets "[]", the first pair should be replaced with round ones "()"
Back Up (Feat. xx) [Album Version]
Is it possible to create such action (expression) ?
I did find a similar post that does the reverse of what I want so maybe it could be adopted to my needs.
[Brackets HELP](https://community.mp3tag.de/t/12867/3)
Thanks!
---
### Author:  [@ohrenkino](https://community.mp3tag.de/u/ohrenkino)
#### Post date: [December 13, 2016, 7:58am UTC](https://community.mp3tag.de/t/brackets-help/18516/2 "2016-12-13T07:58:28Z")
> [@Rufud](#):
>
> ...I did find a similar post that does the reverse of what I want so maybe it could be adopted to my needs.
Original from the thread:
$regexp(%TITLE%,'^([^(]+?)\s(([^(]+?))\s(([^(]+?))$','$1 ($2) [$3]')
My suggestion:
$regexp(%TITLE%,'^([^(]+?)\s[([^(]+?)]\s[([^(]+?)]$','$1 ($2) [$3]')
---
### Author:  [@rufus](https://community.mp3tag.de/u/rufus)
#### Post date: [December 13, 2016, 8:26am UTC](https://community.mp3tag.de/t/brackets-help/18516/3 "2016-12-13T08:26:58Z")
> [@ohrenkino](#):
>
> Original from the thread:
> $regexp(%TITLE%,'^([^(]+?)\s(([^(]+?))\s(([^(]+?))$','$1 ($2) [$3]')
> My suggestion:
> $regexp(%TITLE%,'^([^(]+?)\s[([^(]+?)]\s[([^(]+?)]$','$1 ($2) [$3]')
This does not work, it gives me a regex error:-
REGEXP ERROR: Regular expression
Found a closing ) with no corresponding openening parenthesis. The error occurred while parsing the regular expression fragment: ')s[([^(]+?\>\>\>HERE\>\>\>)]s[([^(]+'.
---
### Author:  [@ohrenkino](https://community.mp3tag.de/u/ohrenkino)
#### Post date: [December 13, 2016, 8:32am UTC](https://community.mp3tag.de/t/brackets-help/18516/4 "2016-12-13T08:32:00Z")
> [@Rufud](#):
>
> This does not work, it gives me a regex error:-
>
> REGEXP ERROR: Regular expression
>
> Found a closing ) with no corresponding openening parenthesis. The error occurred while parsing the regular expression fragment: ')s[([^(]+?\>\>\>HERE\>\>\>)]s[([^(]+'.
Copy & Paste error?
I just tested it with the Tag-Tag-Converter:
$regexp('Back Up [Feat. xx] [Album Version]','^([^(]+?)\s[([^(]+?)]\s[([^(]+?)]$','$1 ($2) [$3]')
and it leads to
Back Up (Feat. xx) [Album Version]
---
### Author:  [@rufus](https://community.mp3tag.de/u/rufus)
#### Post date: [December 13, 2016, 8:32am UTC](https://community.mp3tag.de/t/brackets-help/18516/5 "2016-12-13T08:32:13Z")
> [@Rufud](#):
>
> This does not work, it gives me a regex error:-
>
> REGEXP ERROR: Regular expression
>
> Found a closing ) with no corresponding openening parenthesis. The error occurred while parsing the regular expression fragment: ')s[([^(]+?\>\>\>HERE\>\>\>)]s[([^(]+'.
I see the problem, the forum or a human has lost the double backslashes.
Your code does work with double backslashes.
1=$regexp(%TITLE%,'^([^(]+?)\\s\\[([^(]+?)\\]\\s\\[([^(]+?)\\]$','$1 ($2) [$3]')
Thanks!
---
### Author:  [@rufus](https://community.mp3tag.de/u/rufus)
#### Post date: [December 13, 2016, 8:33am UTC](https://community.mp3tag.de/t/brackets-help/18516/6 "2016-12-13T08:33:51Z")
> [@Rufud](#):
>
> I see the problem, the forum or a human has lost the double backslashes.
>
> Your code does work with double backslashes.
>
> 1=$regexp(%TITLE%,'^([^(]+?)\\s\\[([^(]+?)\\]\\s\\[([^(]+?)\\]$','$1 ($2) [$3]')
>
> Thanks!
I have been editing the .mta action file directly with a text editor, double slashes work.
---
### Author:  [@system](https://community.mp3tag.de/u/system)
#### Post date: [February 9, 2026, 12:26pm UTC](https://community.mp3tag.de/t/brackets-help/18516/7 "2026-02-09T12:26:34Z")