contradictory change

gistfile1.txt

;; contradictory: Filter/c Filter/c -> boolean?
;; Returns true if the AND of the two filters is equivalent to Bot

;; OLD contradictory? definition
(define (contradictory? f1 f2)
  (match* (f1 f2)
    [((TypeFilter: t1 p) (NotTypeFilter: t2 p))
     (subtype t1 t2)]
    [((NotTypeFilter: t2 p) (TypeFilter: t1 p))
     (subtype t1 t2)]
    [((Bot:) _) #t]
    [(_ (Bot:)) #t]
    [(_ _) #f]))
    
    
;; New contradictory? definition
(define (contradictory? f1 f2)
  (match* (f1 f2)
    [((TypeFilter: t1 p) (NotTypeFilter: t2 p))
     (subtype t1 t2)]
    [((NotTypeFilter: t2 p) (TypeFilter: t1 p))
     (subtype t1 t2)]
    [((TypeFilter: t1 p) (TypeFilter: t2 p)) ;; NEW
     (not (overlap t1 t2))]                  ;; NEW
    [((Bot:) _) #t]
    [(_ (Bot:)) #t]
    [(_ _) #f]))