1 files changed, 15 insertions, 14 deletions
diff --git a/control/monad/state.scm b/control/monad/state.scm
index 7e81b38..a8e7775 100644
--- a/control/monad/state.scm
+++ b/control/monad/state.scm
@@ -40,25 +40,26 @@
     (let ((st-list-b ((proc a) st-list-a)))
       ((proc b) st-list-b))))
 
-(define (return-state v)
+(define-syntax define-stateful
+  (syntax-rules ()
+    ((_ ((proc args ...) st) body ...)
+     (define (proc args ...)
+       (make-state
+        (lambda (st) body ...))))))
+
+(define-stateful ((return-state v) st-list)
   "Sets the return value to v"
-  (make-state
-   (lambda (st-list)
-     (cons v (cdr st-list)))))
+  (cons v (cdr st-list)))
 
-(define (get)
+(define-stateful ((get) st-list)
   "Sets the return value of state to st."
-  (make-state
-   (lambda (st-list)
-     (match st-list
-       ((_ st)
-        (list st st))))))
+  (match st-list
+    ((_ st)
+     (list st st))))
 
-(define (put v)
+(define-stateful ((put v) st-list)
   "Sets st to v."
-  (make-state
-   (lambda (st-list)
-     (list '() v))))
+  (list '() v))
 
 (define-method (run-state st-proc init)
   "Exec state with init as starting state value and st."