Dear guile, The following program should just return 'foo, but it enters an infinite loop:
(use-modules (oop goops)) (define-class <my-generic> (<generic>)) (define-method (no-method (generic <my-generic>) args) 'foo) (define-method (no-applicable-method (generic <my-generic>) args) 'foo) (define hello (make <my-generic> #:name 'hello)) (hello) I don’t know GOOPS enough to understand what happens, but when I slightly change the last line: (use-modules (oop goops)) (define-class <my-generic> (<generic>)) (define-method (no-method (generic <my-generic>) args) 'foo) (define-method (no-applicable-method (generic <my-generic>) args) 'foo) (define hello (make <my-generic> #:name 'hello)) (apply-generic hello '()) Now it returns 'foo, as expected. So my guess is that the infinite loops happens during the memoization phase. More specifically, the no- applicable-method is called over and over again. Please find a failing test case attached. Best regards, Vivien
From 435d4d7569a25dda05489c3eda3086e0dbf531af Mon Sep 17 00:00:00 2001 From: Vivien Kraus <viv...@planete-kraus.eu> Date: Tue, 21 Sep 2021 11:40:43 +0200 Subject: [PATCH] goops: cannot override no-applicable-method for a generic that has no methods --- test-suite/tests/goops.test | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/test-suite/tests/goops.test b/test-suite/tests/goops.test index b06ba98b2..626eeaacd 100644 --- a/test-suite/tests/goops.test +++ b/test-suite/tests/goops.test @@ -761,3 +761,22 @@ #:metaclass <redefinable-meta>))) (pass-if-equal 123 (get-the-bar (make <foo>))) (pass-if-equal 123 (get-the-bar (make <redefinable-foo>)))))) + +(with-test-prefix "Can override no-applicable-method in a generic without methods" + (let ((patience-no-method 10) + (patience-no-applicable-method 10)) + (define-class <my-generic> (<generic>)) + (define-method (no-method (generic <my-generic>) args) + (when (= patience-no-method 0) + (error "Infinite loop detected in no-method")) + (set! patience-no-method (- patience-no-method 1)) + 'foo) + (define-method (no-applicable-method (generic <my-generic>) args) + (when (= patience-no-applicable-method 0) + (error "Infinite loop detected in no-applicable-method")) + (set! patience-no-applicable-method (- patience-no-applicable-method 1)) + 'foo) + (define hello + (make <my-generic> + #:name 'hello)) + (pass-if-equal (hello) 'foo))) -- 2.33.0