Ludovic Courtès <l...@gnu.org> writes: > Or maybe like this: > > (define (make-critical-section . args) > "Return a channel used to implement a critical section. That channel can > then be passed to 'join-critical-section', which will ensure sequential > ordering. ARGS are the arguments of the critical section. > > Critical sections are implemented by passing the procedure to execute to a > dedicated fiber." > (let ((channel (make-channel))) > (spawn-fiber > (lambda () > (let loop () > (match (get-message channel) > (((? channel? reply) . (? procedure? proc)) > (put-message reply (apply proc args)))) > (loop)))) > channel)) > > (define (call-with-critical-section channel proc) > "Call PROC in the critical section corresponding to CHANNEL. Return the > result of PROC." > (let ((reply (make-channel))) > (put-message channel (cons reply proc)) > (get-message reply))) > > That makes it clear that the reply channel is used only by the calling > fiber.
I like it, but in that case MAKE-CHANNEL is called every time CALL-WITH-CRITICAL-SECTION is called. Do you think it is a significant overhead? Clément
