As noted in Programming Perl in the 'Common Goofs for Novices' section:
"Not saving $1, $2, and so on, across regular expressions. Remember that every new m/atch or s/ubsti/tute/ will set (or clear, or mangle) your $1, $2... variables, as well as $`, $', and $&..."

I imagine Perl has to do this in order for backreferences, e.g. /blah(\w+)blah\1/, to work.

In reply to Re: Another regex variable puzzle by archon
in thread Another regex variable puzzle by Rudif

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