The following works, but you risk injecting commands into your script. To do it properly, you'd have to do the variable interpolation yourself.

my ($reg, $reg2) = @ARGV;
my $string = "how1=on&how2=on";

$string =~ s/$reg/ eval "\"$reg2\"" /eg;
print $string;

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In reply to Re: Help with Regexp substitution using variables by ikegami
in thread Help with Regexp substitution using variables by kwokna

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