Hi, I'm trying to write an application that takes 2 regular expressions as input, and then do a substitution on a file. The problem happens when I try to use the memory variable as the second substitution. The resulting output becomes the literal '$1' as opposed to the match in parenthesis. It's better to look at the code. 
my ($reg, $reg2) = @ARGV;
my $string = "how1=on&how2=on";

$string =~ s/$reg/$reg2/eg;
print $string;

[download]
Input: perl test.pl how(\d)=on why$1=off
What I want the ouput to be is: why1=on&why2=on
What I actually get is: why$1=off&why$1=off.
Any help is greatly appreciated!
Thanks,
Nathan

In reply to Help with Regexp substitution using variables by kwokna

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