use strict;
use warnings;

no warnings 'redefine';

for (
   [ "Symbol,  use utf8: " => "use utf8; sub ∃    {}" ],
   [ "Symbol,  no  utf8: " => "no  utf8; sub ∃    {}" ],
   [ "Russian, use utf8: " => "use utf8; sub трщь {}" ],
   [ "Russian, no  utf8: " => "no  utf8; sub трщь {}" ],
) {
   print $_->[0], eval "$_->[1]; 1" ? "Success\n" : $@;
}

##</code><code>##

Symbol,  use utf8: Illegal declaration of anonymous subroutine at (eval 1) line 1.
Symbol,  no  utf8: Illegal declaration of anonymous subroutine at (eval 2) line 1.
Russian, use utf8: Success
Russian, no  utf8: Illegal declaration of anonymous subroutine at (eval 4) line 1.