"Untainting" variables just means assigning an untainted value to it.
Hint. It's the value that tainted, not the variable.
Hint. If I write untainted value, I know.

Hint: Look back. You'll see that you were the first & only one to mention "Untainting" variables.

As for your "Really? In Perl land, there isn't such a thing as "untainting"., I guess you'd best re-read perlsec:

The lesson is that when untainting, you must be exceedingly careful with your patterns. Laundering data using regular expression is the only mechanism for untainting dirty data, ...
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
RIP an inspiration; A true Folk's Guy

In reply to Re^5: use re 'taint' with s/// operator by BrowserUk
in thread use re 'taint' with s/// operator by Pirax

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