Masatake YAMATO
yamat****@redha*****
2010年 2月 6日 (土) 15:17:57 JST
こんにちは
hash-table-push!に対してhash-table-pop!があるように
slot-push!に対してslot-pop!があると便利だと思います。
追加を検討してもらえないでしょうか？
大和
(define (slot-pop! obj slot . default)
(if (and (not (null? default))
(or (not (slot-bound? obj slot))
(null? (slot-ref obj slot))))
(car default)
(let ((r (slot-ref obj slot)))
(slot-set! obj slot (cdr r))
(car r))))
(use gauche.test)
(test-start "slot-pop!")
(test-section "no default value")
(define-class <x> () ((a :init-value '())))
(define-class <y> () (a))
(test* "() push pop" 1
(let1 x (make <x>)
(slot-push! x 'a 1)
(slot-pop! x 'a)))
(test* "() push push pop pop" 1
(let1 x (make <x>)
(slot-push! x 'a 1)
(slot-push! x 'a 2)
(slot-pop! x 'a)
(slot-pop! x 'a)))
(test-section "with default value")
(test* "()" 1
(let1 x (make <x>)
(slot-pop! x 'a 1)))
(test* "<unbound>" 1
(let1 x (make <y>)
(slot-pop! x 'a 1)))
(test* "<broken value>" <y>
(let1 x (make <y>)
(guard (e (else (class-of x)))
(slot-set! x 'a 1)
(slot-pop! x 'a 2))))
(test-end)