in reply to umlauts, special chars in perl regular expressions

If you're using a 5.8-series of Perl, the input will be automatically detected as Unicode and Do The Right Thing. With a 5.6-series Perl, you need to add use utf8;. Anything lower than 5.6 probably won't handle it at all.

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: () { :|:& };:

Note: All code is untested, unless otherwise stated