ok 1 - use Divisor;
ok 2 - The object isa Divisor
ok 3 - Seven divides 42.
ok 4 - The year does not contain a whole number of weeks.
ok 5 - But the Gregorian calendar repeats itself every 400 years.
ok 6 - The object isa Divisor
ok 7 - Two divides '42'.
ok 8 - Two does not divide '19'.
not ok 9 - Two divides 222222222222222222222222222222222222222222222222222222222
22222222222222222222222222222222222222222222222222222222222222222222222222222222
22222222222222222222222222222222222222222222222222222222222222222222222222222222
22222222222222222222222222222222222222222222222222222222222222222222222222222222
22222222222222222222222. # TODO Redefine divisibility by two.
#     Failed (TODO) test (Divisor.t at line 32)
# We just contrived an overflow exception.
ok 10 - Divisor->can('set_divisibility_test')
ok 11 - Two divides '42'.
ok 12 - Two does not divide '19'.
ok 13 - Two divides 222222222222222222222222222222222222222222222222222222222222
22222222222222222222222222222222222222222222222222222222222222222222222222222222
22222222222222222222222222222222222222222222222222222222222222222222222222222222
22222222222222222222222222222222222222222222222222222222222222222222222222222222
22222222222222222222, as any fool can see.