I too use a dedicated App for batch file renaming. There are so many possible patterns to batch renaming files that it seems like it's a perfect task for a small App that has been written to do only that task (and gives you the chance to preview before committing to the changes). For years and years I have been using A Better Finder Rename which is now on version 11.
You can do this without using regular expressions.
If you get the name of a file into a KM variable. For example set fname to 10536-SLATE-Jun-BC-72 then you can treat the variable as a KM Array Variable with a custom delimiter.
In this example %Variable%fname[1]-% will return the value 10536
and %Variable%fname[2]-% will return the value SLATE
and so on.
You can then reconstruct the file name that you want by stringing together the date fragments with the bits you want to keep. For example:
In addition to all these more than adequate replies, let me point out there was a discussion about this a while ago that led to both Perl and JavaScript Keyboard Maestro macros. You can specify a regex to parse the existing selected file names and you'll see a preview of the change, which you can sign off on or modify on the fly. I've used the Perl version since.
The prompt (with the regex for your case) would look like this:
I bought Name Mangler last month and like it a lot, but I often need to select files in the Finder and rename them quickly and I find that opening a separate app and entering in a bunch of specific info for finding and replacing slows me down.
I'm back at my Mac so I thought I'd help out by posting an example macro for you. It will do what you've asked but, as with any macro supplied to you by someone else, you need to test it on some files that are copies/not important just to verify it does what you want it to.
You start by selecting the files of interest in Finder and then trigger this macro. It will then prompt you to enter your "code" and the date will be set to the current month - which you can change if you wish.
I've used Local variables throughout which then get deleted when the macro finishes - thereby avoiding clogging up your installation of KM with unwanted variables.
For safety, the macro is uploaded in a disabled state.
and can't figure this out for the life of me.
+1 for Name Mangler. It’s a great utility but it really shines when renaming batches of thousands of files which it does somehow in a few seconds!
