I have a case where I'm taking user input and feeding it to perl code in the following format: 
  $str =~ s/$match/$repl/;

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where $str, $match, and $repl are strings fed to me by my user. Ignoring the security implications of this (I know there are plenty), I cannot get perl to recognize "\1" or "$1" sequences in the $repl variable.

For example, if $str contains "abc", $match contains "(a)(.)", and $repl contains "\2\1", $str ends up containing "\2\1c" instead of "bac", as intended.

Is there any way to force s/// to process this like I want?

In reply to How do you get s/// to look inside variables in the replacement string? by markkawika

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