- (case op
- (('start-timer)
- (set! start (SDL_GetTicks))
- (set! state 'running))
- (('stop-timer)
- (set! state 'stopped))
- (('get-time)
- (cond ((eq? state 'stopped) 0)
- ((eq? state 'paused) paused)
- (else (- (SDL_GetTicks) start))))
- (('pause-timer)
- (cond ((eq? state 'running)
- (set! paused (- (SDL_GetTicks) start))
- (set! state 'paused))))
- (('resume-timer)
- (cond ((eq? state 'paused)
- (set! start (- (SDL_GetTicks) paused))
- (set! state 'running))))))))
+ (cond ((eq? op 'start-timer)
+ (set! start (SDL_GetTicks))
+ (set! state 'running))
+
+ ((eq? op 'stop-timer)
+ (set! state 'stopped))
+
+ ((eq? op 'get-time)
+ (cond ((eq? state 'stopped) 0)
+ ((eq? state 'paused) paused)
+ (else (- (SDL_GetTicks) start))))
+
+ ((eq? op 'get-state)
+ state)
+
+ ((eq? op 'pause-timer)
+ (cond ((eq? state 'running)
+ (set! paused (- (SDL_GetTicks) start))
+ (set! state 'paused))))
+
+ ((eq? op 'resume-timer)
+ (cond ((eq? state 'paused)
+ (set! start (- (SDL_GetTicks) paused))
+ (set! state 'running))))))))
+
+(define (start-timer timer)
+ (timer 'start-timer))
+
+(define (stop-timer timer)
+ (timer 'stop-timer))
+
+(define (get-time timer)
+ (timer 'get-time))
+
+(define (get-state timer)
+ (timer 'get-state))
+
+(define (pause-timer timer)
+ (timer 'pause-timer))
+
+(define (resume-timer timer)
+ (timer 'resume-timer))