I want a substitution with a Perlvar of the nth match, if one exists?

If I understand your question correctly, then no, no such perlvar that keeps track of "how many" regexes have been executed/replaced exists, and you'll have to use one of the other methods you described. Update: Or the clever hack by choroba.

In reply to Re: Perl substitute with the nth match by haukex
in thread Perl substitute with the nth match by misterperl

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