RegEx

Madhu Desai · 05-20-2020, 09:07 AM

Hello All

I'm using RegEx to rename a lot of files. Following are some samples of the filename.

Code:

$ ls -1N
01 Linux OS Introduction12m 58s.mp4
02 Subject Intro25s.mp4
03 Learning Objectives23s.mp4
04 Final Analysis3m 12s.mp4

I want to replace characters in bold to nothing. So, the regular expression I'm using is this. I'm also using Positive Lookahead Assertion for safety.

Code:

([0-9]{1,2}[sm]{1}) ?([0-9]{1,2}[sm]{1})?(?=\.mp4$)

Code:

$ prename -nv 's/([0-9]{1,2}[sm]{1}) ?([0-9]{1,2}[sm]{1})?(?=\.mp4$)//' *.mp4
01 Linux OS Introduction12m 58s.mp4 -> 01 Linux OS Introduction.mp4
02 Subject Intro25s.mp4 -> 02 Subject Intro.mp4
03 Learning Objectives23s.mp4 -> 03 Learning Objectives.mp4
04 Final Analysis3m 12s.mp4 -> 04 Final Analysis.mp4

Is this the correct way? Or can I optimize/shorten RegEx even better?

Thanks

shruggy · 05-20-2020, 09:16 AM

Maybe

Code:

(\d\d?[sm] ?){1,2}(?=\.mp4$)

pan64 · 05-20-2020, 09:39 AM

probably in two steps:

Code:

\d+s\.mp4 -> .mp4
\d+m \.mp4 -> .mp4
# or
(\d+m )?\d+s\.mp4 -> .mp4