(define (is-a? obj class)
(and (memq class (class-precedence-list (class-of obj))) #t))
-
-;;; The standard class precedence list computation algorithm
-;;;
-;;; Correct behaviour:
-;;;
-;;; (define-class food ())
-;;; (define-class fruit (food))
-;;; (define-class spice (food))
-;;; (define-class apple (fruit))
-;;; (define-class cinnamon (spice))
-;;; (define-class pie (apple cinnamon))
-;;; => cpl (pie) = pie apple fruit cinnamon spice food object top
-;;;
-;;; (define-class d ())
-;;; (define-class e ())
-;;; (define-class f ())
-;;; (define-class b (d e))
-;;; (define-class c (e f))
-;;; (define-class a (b c))
-;;; => cpl (a) = a b d c e f object top
-;;;
-
(define (compute-std-cpl c get-direct-supers)
+ "The standard class precedence list computation algorithm."
(define (only-non-null lst)
(filter (lambda (l) (not (null? l))) lst))
c-direct-supers)
(list c-direct-supers))))))
-;; Bootstrap version.
+;; This version of compute-cpl is replaced with a generic function once
+;; GOOPS has booted.
(define (compute-cpl class)
(compute-std-cpl class class-direct-supers))
(pass-if-equal 100 (slot-ref a 'test))
(pass-if-equal 100 (slot-ref b 'test))
(pass-if-equal 200 (slot-ref c 'test)))))))
+
+(define-class <food> ())
+(define-class <fruit> (<food>))
+(define-class <spice> (<food>))
+(define-class <apple> (<fruit>))
+(define-class <cinnamon> (<spice>))
+(define-class <pie> (<apple> <cinnamon>))
+
+(define-class <d> ())
+(define-class <e> ())
+(define-class <f> ())
+(define-class <b> (<d> <e>))
+(define-class <c> (<e> <f>))
+(define-class <a> (<b> <c>))
+
+(with-test-prefix "compute-cpl"
+ (pass-if-equal "<pie>"
+ (list <pie> <apple> <fruit> <cinnamon> <spice> <food> <object> <top>)
+ (compute-cpl <pie>))
+
+ (pass-if-equal "<a>"
+ (list <a> <b> <d> <c> <e> <f> <object> <top>)
+ (compute-cpl <a>)))