Hi

in scripts I usually match like this: 

my ($match) = $string =~ /$regex/;

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but sometimes I do one-liners like this: 
perl -ne '/$regex/, $SUM += $1; END { print $SUM }' file.txt

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In this context I was just bitten by the (documented) behaviour that a failed match does not reset the match variables which in my case lead to a wrong sum as on empty lines where the regex did not match the previous match was (again) added to the sum.

For curiosity's sake now:

Assuming I did not want to introduce new variables but use $1 etc: How would I reset these variables to avoid the wrong sum as both "undef $1" as "$1=undef" does not work?

In reply to reset of match variables by morgon

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