I have written a program which can load regular expressions from a user designated file containing expressions in a standardized format, but it does not work successfully with all legal expressions. I would like to determine if there is a way to have the following expressions parsed appropriately to achieve the desired result of finding a 'shebang' line and inserting a usage line for the English module, (surrounded by two blank lines!)

Here's a copy of an 'LTL'-separated line which I am loading from a file containing a hash key, a search expression, and a replace expression: 

"
(^\#!/usr/bin/perl[^\n]*\n)LTL(^\#!/usr/bin/perl[^\n]*\n)LTL(^\#!/usr/
+bin/perl[^n]*n)LTL${
"

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When loaded into my code it yields: 
 
$regExpKey          = (^\#!/usr/bin/perl[^\n]*\n)
$searchPattern      = (^\#!/usr/bin/perl[^\n]*\n)
$replacementPattern = ${^MATCH}\x0Ause English \( no_match_vars \);\x0
+A

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When I slurp the file to be searched into the $content variable I execute 
 
$content =~ s{$searchPattern}{${^MATCH}$replacementPattern}gxms;

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and it $content becomes the following: 
"
${^MATCH}\x0Ause English \( no_match_vars \);\x0A
"

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e.g. ${^MATCH} is not interpolated(?) and the newlines, (\x0A), are not inserted, even if I were to use "\n"'s!

Please help me understand whether or not what I am attempting is doable and/or practical and, if so, how do I rectify what I am doing in error?

20090605 Janitored by Corion: Added formatting, code tags, as per Writeup Formatting Tips

In reply to how to load regular expressions from a file by lloder174

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