not=?

[procedure] =? [compare] [x y]

[procedure] <? [compare] [x y]

[procedure] >? [compare] [x y]

[procedure] <=? [compare] [x y]

[procedure] >=? [compare] [x y]

[procedure] not=? [compare] [x y]

SRFI-67: If the values x and y are given, test if x and y are in the relation specified by the name of the procedure rel?, with respect to compare procedure compare; otherwise construct a predicate procedure.

In the forms (rel? [compare] x y), the result is a boolean (either #t or #f) depending on (compare x y) and the test rel? as specified for if<? etc. If compare is not supplied, default-compare is used.

In the form (rel? [compare]), the predicate procedure (lambda (x y) (rel? compare x y)) is constructed. Again, if compare is not supplied, default-compare is used.