c:\@Work\Perl\monks>perl -wMstrict -le
"my $re_obj = qr{([0-6BS])};
 if (ref $re_obj) {
   print 'A: reference: ', ref $re_obj;
   }
 else {
   print 'A: not a reference';
   }
 ;;
 my $re_str = '' . $re_obj;
 if (ref $re_str) {
   print 'B: reference: ', ref $re_str;
   }
 else {
   print 'B: not a reference';
   }
"
A: reference: Regexp
B: not a reference