Don't be afraid to put non ASCII characters in your source code. Use UTF-8 (which you are probably already doing anyway since the curly quotes aren't available in too many other encodings) and put this pragma in your source code:

use utf8;
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This is encouraged! From the utf8 manpage:

The "use utf8" pragma tells the Perl parser to allow UTF-8 in the program text in the current lexical scope (allow UTF-EBCDIC on EBCDIC based platforms). The "no utf8" pragma tells Perl to switch back to treating the source text as literal bytes in the current lexical scope.

This pragma is primarily a compatibility device. Perl versions earlier than 5.6 allowed arbitrary bytes in source code, whereas in future we would like to standardize on the UTF-8 encoding for source text.