Hi, I want to use scalar variables which store regular expressions while using string substitution. For Example: 
$_ = "master442arb_ba";
$rule = "master\(.*\)arb_ba";
$action = "m\$1a_ba";
s/$rule/$action/;
#s/master(.*)arb_ba/"m${1}a_ba"/;
print $_;

[download]

The correct output is "m442a_ba". The commented s/// command gives the correct
output but if I try the same thing with the $rule and $action variables,
it gives "m$1a_ba" as the output. Can someone explain why and what would be the correct expression?

Thanks!

In reply to Using scalar variables as substitution regular expression by addy7de

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