my $d_1 = 0.1e0; # double 0.1 ( == 3602879701896397/36028797018963968 ) my $r_1 = 0.1; # rational 1/10 my $d_2 = 0.10000000000000001e0;# double, same value as $d_1 my $r_2 = 0.10000000000000001; # rational 10000000000000001/100000000000000000 # check that $d_1 == 3602879701896397/36028797018963968 say "not ok 0" if $d_1 != 3602879701896397/36028797018963968; # Check that $d_1 != 1 / 10; say "not ok 1" if $d_1 == 1 / 10; # Check that $d_1 and $d_2 are assigned to exactly the same value: say "not ok 2" if $d_1 != $d_2; # Check that $r_ and $r_2 are assigned different values: say "not ok 3" if $r_1 == $r_2; # Since $r_1 and $r_2 are unequal, $d_1 should not be equal to both $r_1 && $r_2. # We check this, interchanging lhs and rhs operands in case that makes a # difference: say "not ok 4" if ($d_1 == $r_1 && $d_1 == $r_2); say "not ok 5" if ($r_1 == $d_1 && $r_2 == $d_1); # Similarly $d_2 should not be equal to both $r_1 and $r_2: say "not ok 6" if ($d_2 == $r_1 && $d_2 == $r_2); say "not ok 7" if ($r_1 == $d_2 && $r_2 == $d_2); say Rat($d_1); say Rat($d_2); #### not ok 1 not ok 4 not ok 5 not ok 6 not ok 7 0.1 0.1