+(defgeneric cn-test (request)
+ (:generic-function-class accept-generic-function)
+ (:method-combination content-negotiation))
+(defmethod cn-test ((request (accept "text/html")))
+ 'html)
+(defmethod cn-test ((request (accept "text/plain")))
+ 'plain)
+(defmethod cn-test ((request (accept "image/webp")))
+ 'webp)
+(defmethod cn-test ((request (accept "audio/mp3")))
+ (call-next-method)
+ 'mp3)
+(defmethod cn-test :after (request)
+ (print 'after))