my $out;
for ($in) {
   pos = 0;
   for (;;) {
      if (/\G ([^\\]+)            /xsgc) { $out .= $1; }
      if (/\G \\u([0-9a-fA-F]{4}) /xsgc) { $out .= chr(hex($1));      next; }
      if (/\G \\([tnfr])          /xsgc) { $out .= $CONTROL_CODE{$1}; next; }
      if (/\G \\(.)               /xsgc) { $out .= $1;                next; }
      if (/\G \z                  /xsgc) {                            last; }
      die;  # Ends with unescaped "\".
   }
}

printf("U+%04x\n", ord($_)) for $out =~ /(.)/sg;

Update: Fixed arrangement of conditions.
Update: Changed /\Z/ to /\z/.

In reply to Re: Regex Parsing Style by ikegami
in thread Regex Parsing Style by Jim

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