@@ -48,9 +48,16 @@
 	(define-macro (rule . body)
 				  (let ([decl (car body)]
 						[patterns (cdr body)])
 					`(define ,decl
-					   (define-macro (@ . tree) (@rewrite-patterns tree))
+					   (define-macro (@ . tree) (@rewrite-patterns tree)) ;choice point
+					   (define-macro (: . tree) (@rewrite-patterns (cons (list "") tree))) ;optional choice
+					   (define-macro (? . tree) (@rewrite-patterns (cons (list "") (list tree)))) ;optional - TODO: rewrite
 					   ,(@rewrite-patterns patterns))))
-
+	; generate simple word-banks
+	(define-macro (bank . body)
+				  (let ([decl (car body)]
+						[patterns (cdr body)])
+					`(define (,decl)
+							 (one-of ,@patterns))))
 	(define (pick ar)
 		(vector-ref ar (pseudo-random-integer (vector-length ar))))