# \_TAG tag function?

**URL:** <https://community.mp3tag.de/t/tag-tag-function/42339>\
**Category:** Support\
**Created:** [July 14, 2018, 7:10am UTC](https://community.mp3tag.de/t/tag-tag-function/42339 "2018-07-14T07:10:35Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![sheepdisease](https://community.mp3tag.de/letter_avatar_proxy/v4/letter/s/d07c76/32.png) [@sheepdisease](https://community.mp3tag.de/u/sheepdisease)\
**Post date:** [July 14, 2018, 7:10am UTC](https://community.mp3tag.de/t/tag-tag-function/42339/1 "2018-07-14T07:10:35Z")

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Hello there, I am looking through some code and don't know where mp3tag is pulling the data from for \_TAG?

For example:

```
T=4
! Title Case Conversion [3] (Articles, Conjunctions & Short Prepositions to Lower-Case, Except Before or After Punctuation)=
F=_TAG
1=(?<!&|:|;|-|/|!|(?<![A-Z]\\.[A-Z])\\.|\\?|\\+)(\\s+\\b(A|An|And|As|At|But|By|De|Et|For|From|In|Into|Le|Nor|Of|Off|On|Onto|Or|So|Than|The|To|Upon|Von|With)(?\u003d\\s)(?!\\s[\\-\\(\\)\\[\\]{}]))
2=$lower($1)
3=1

```

 ![image](https://community.mp3tag.de/uploads/default/original/2X/f/f67b5c10f7450bcf8b11247b6cc0ae3f66dc0d72.png)

---

<div class="post-metadata">

**Author:** ![system](https://community.mp3tag.de/uploads/default/original/2X/c/ce7035d426cb755a7916793326d23b465222a407.png) [@system](https://community.mp3tag.de/u/system)\
**Post date:** [February 9, 2026, 12:27pm UTC](https://community.mp3tag.de/t/tag-tag-function/42339/2 "2026-02-09T12:27:32Z")

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