racket/collects/lang/private/imageeq.ss
2008-12-29 22:36:53 +00:00

20 lines
582 B
Scheme

(module imageeq mzscheme
(require mred
mrlib/cache-image-snip
mzlib/class)
(provide image? image=?
coerce-to-cache-image-snip
snip-size
bitmaps->cache-image-snip)
(define (image? a)
(or (is-a? a image-snip%)
(is-a? a cache-image-snip%)))
(define (image=? a-raw b-raw)
(unless (image? a-raw) (raise-type-error 'image=? "image" 0 a-raw b-raw))
(unless (image? b-raw) (raise-type-error 'image=? "image" 1 a-raw b-raw))
;; Rely on image-snip% implementing equal<%>:
(equal? a-raw b-raw)))