scsh-0.6/scheme/debug/test-generic.scm

35 lines
667 B
Scheme

; Copyright (c) 1993-1999 by Richard Kelsey and Jonathan Rees. See file COPYING.
(define g-methods (make-method-table 'g))
(define g (make-generic g-methods))
(define foo-family (make-family 'foo 1))
(define-method g-methods foo-family
(lambda (x)
(if (even? x)
'win
(fail))))
(define bar-family (make-family 'bar 2)) ;More specific
(define-method g-methods bar-family
(lambda (x)
(case x
((1 3 5) 'ok)
(else (fail)))))
(define-method g-methods (make-family 'baz 2) ;Same priority as bar-family
(lambda (x)
(case x
((3) 'great)
(else (fail)))))
; (g 0) => 'win
; (g 1) => 'ok
; (g 3) => 'great
; (g 9) => error