Scripting

I can't find sort of scripting function to search the position of the n-th occurence of character x in string y

Maybe as hidden function ?

I don't want to go into the user-defined meta-tag direction as temporary workfields, as this implies changing the mp3-files

I would also be interested to know if there is a way to write own functions (or actions) useable from within scripting, this to be able to shorten tag-filename strings which are so long they aren't maintainable anymore.

Thx

Me too.
But for what is it worth?
Can you provide a real life example?
Maybe there is already some way to solve this task with Mp3tag scripting functions.

Just to be informed ... how would this work?

No, there is no possibility to write user defined functions.
Yes, there is the possibility to set up user defined actions (the main strength of Mp3tag), which can be arranged in groups of actions, which can be set up to groups of groups.

DD.20120210.1706.CET

Here you go:
n-th occurence of character x in string xyzxyzxyzxyzxyz

$regexp($sub($strstr($regexp(xyzxyzxyzxyzxyz,^((.*?x){n}),$1@@@),@@@),1),^-1$,0)

n = 1 => output = 1
n = 2 => output = 4
n = 3 => output = 7
n = 4 => output = 10
n = 5 => output = 13
n = 6 (or higher) => output = 0 (= not found)

x = a (or anything not in the string) => output = 0 (= not found)

You can change the output for "not found" by replacing the "0" at the last postion the format string.