vroom wrote: 
                  cd directory_of_PerlTidy
                  perl perltidy -io -i=3 path_to_script_to _be_formatt
+ed

[download]
I keep the above in a comment in the script it's used in. There should be a feature to automatically insert such a comment,
If there's some boiler-plate that you want to appear in all of your code, you need an emacs templating system, such as template.el:
http://emacs-template.sourceforge.net/
I've been working on an emacs lisp package to use template.el with perl, which I call "perlnow.el":
http://obsidianrook.com/perlnow
Even if you don't want to use my code, you might like to look at the template.el templates there that I set-up to use for perl code.

(Briefly: perlnow.el is designed to automate some routine tasks in perl programming: jumping into writing code, doing a "compile/check" on the code, jumping into writing tests for your code, running the tests, and so on. I've been finding it useful, but I'm still turning up minor bugs.)

with a time stamp of when it was tidied.
There I can't help you much off hand, you'll need to do some hackery of your own, either in perl or elisp.

What I would probably do is write some elisp similar to what rhythmicus posted: it wouldn't be too hard to write an emacs extension that would do a perltidy on the current buffer, and insert or update a standard comment with a timestamp for when perltidy was run.

20040810 Edit by ysth: move </i> out of <blockquote>

In reply to Re^4: Specific Indentation request for perl in Emacs by doom
in thread Specific Indentation request for perl in Emacs by Yoyoson

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