goops and equal?

[Jan Nieuwenhuizen]

Hi,

In the example below, my implementation of equal? is only being 
used if both types are the same.  That surprised me; the manual
says equal? becomes a generic and for normal generics this works
as I expect.

How do I get the magic equal? to do what show the same result as the
simple generic type-equal?

And also, do we want such surprises?

Greetings,
Jan

(read-set! keywords 'prefix)
(use-modules (oop goops))

(define-class <type> ()
  (name :accessor .name :init-value #f :init-keyword :name))

(define-method (equal? (a <type>) (b <type>))
  (display "<type>equal?\n")
  (eq? (.name a) (.name b)))

(define-method (equal? (a <type>) (b <symbol>))
  (display "<type0>equal?\n")
  (eq? (.name a) b))

(define-method (type-equal? (a <type>) (b <symbol>))
  (display "<type1>equal?\n")
  (eq? (.name a) b))

(format #t "equal?: ~a\n" (equal? (make <type> :name 'a) (make <type> :name 
'a)))
(newline)
(format #t "equal?: ~a\n" (equal? (make <type> :name 'a) 'a))
(newline)
(format #t "type-equal?: ~a\n" (type-equal? (make <type> :name 'a) 'a))
(newline)


-- 
Jan Nieuwenhuizen <address@hidden> | GNU LilyPond http://lilypond.org
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