Here's a problem that has dogged me for years. I want to be able to define a string that contains regex criteria, and then use that within an actual regex expression. For example: 

$criteria = "(abc|123)\$";
$teststring = "Foo walks up and says: abc";

if ( $teststring =~ /$criteria/ ) {
      print "it worked!\n";
}

[download]

Problem is, it doesn't work. A workaround is to not use the parenthesis in the $criteria and instead do: 
$teststring =~ /($criteria)/

[download]
....but that seems like a hack. Is there a better way to do this aside from eval (which has its own problems, particularly if $criteria is being defined through a user-specified value from a web page).

thanks
Nept

In reply to $scaler inside a RegEx by ManFromNeptune

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