>perl -le"print( undef eq '' )" 1 >perl -le"print( 123 eq '123' )" 1 >perl -le"$r=\$s; print( $r eq sprintf('SCALAR(0x%x)', 0+$r) )" 1 >perl -le"print( qr/a/ eq '(?-xism:a)' )" 1 etc