coops: define-method does not redefine

[megane]

Below are two cases, first works as expected, second doesn't.

Case 1
(require-extension coops)

(define-class <a> ())

(define b (make <a>))

(define-method (foo (c <a>))

(print "foo v1 on " c))

(define-method (foo (c <a>))

(print "foo v2 on " c))

(foo b)

;; Output:
;; foo v2 on #<coops instance of `<a>'>

Case 2
(require-extension coops)

(define-class <a> ())

(define a (make <a>))

(define-method (foo (a <a>))

(print "foo v1 on " a))

(foo a)

(define-method (foo (a <a>))

(print "foo v2 on " a))

(foo a)

;; Output:
;; foo v1 on #<coops instance of `<a>'>
;; foo v1 on #<coops instance of `<a>'> <-- nothing changed

[megane]

You can get the desired effect when using modules. In this case some trickery is needed to not redefine the classes.

(require-extension coops)

(module cls

*
(import chicken scheme)
(use coops)

(define-class <a> ()))

(import cls)
(define a (make <a>))

;; foo v1
(module modu

*
(import chicken scheme)
(use coops)

(import cls)

(define-method (foo (a <a>))

(print "foo v1 on " a)))

(import modu)

(foo a)

;; foo v2
(module modu

*
(import chicken scheme)
(use coops)

(import cls)

(define-method (foo (a <a>))

(print "foo v2 on " a)))

(foo a)

;; Output:
;; foo v1 on #<coops instance of `<a>'>
;; foo v2 on #<coops instance of `<a>'>

[megane]

Here's a small variation of last comment that doesn't work:

(require-extension coops)

(module cls

*
(import chicken scheme)
(use coops)

(define-class <a> ())

(define-method (foo (a <a>))

(print "foo v1 on " a)))

(import cls)
(define a (make <a>))

(foo a)

;; foo v2
(module modu

*
(import chicken scheme)
(use coops)

(import cls)

(define-method (foo (a <a>))

(print "foo v2 on " a)))

(import modu)
(foo a)

;; Output:
;; foo v1 on #<coops instance of `<a>'>
;; foo v1 on #<coops instance of `<a>'>

[felix winkelmann]

This is caused by overeager caching of the method (building coops with -feature no-cache appears to make the exmaple work). I'll try to find a solution to this.

[felix winkelmann]

I have added an additional cache check, effctively invalidating method caches when a method is defined or re-defined. See coops 0.8 which seems to run your example ok.