These procedures return comparators whose functions behave as follows:
- The type test returns #t in all cases.
- The equality functions are eq?, eqv?, and equal? respectively.
- The ordering function is implementation-defined, except that it must conform to the rules for ordering functions. It may signal an error instead.
- The hash function is default-hash.
These comparators accept circular structure (in the case of equal-comparator, provided the implementation's equal? predicate does so) and NaNs.