Hi. I'm dealing with a problem where hexadecimal character references such as '\x{FEFF}' and 'chr(0xFEFF)' are ignored when they appear inside a regex expression.

However, I can copy hexidecimal or decimal references into a Perl variable, insert that variable into a regex, and then it works. Here's an example: 

  $string = 'ABC';
  $chr65 = chr(65);
  $chr97 = chr(97);

  $string =~ s/$chr65/$chr97/;
  print "$string\n";

  #Input = 'ABC', Output = 'aBC'

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Others seem to be able to quote these references directly inside a regex expression and have them be understood. I'm wondering if I might need to be referencing a specific package name in my script. Can anyone help?

Thanks,

In reply to Hexadecimal character references not understood inside a regex by silentq

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