Rewritten OPTIONALS macro with SYNTAX-RULES.

scheme/httpd/surflets/typed-optionals.scm

@@ -33,32 +33,9 @@
 	    (cdr pred-list)
 	    args)))))
 
-
 (define-syntax optionals
-  (lambda (exp rename compare)
-    (let ((%receive (rename 'receive))
-	  (%typed-optionals (rename 'typed-optionals))
-	  (%list (rename 'list))
-	  (%if (rename 'if))
-	  (%pair? (rename 'pair?))
-	  (%error (rename 'error))
-	  (%let (rename 'let))
-	  (%list-ref (rename 'list-ref))
-
-	  (args (cadr exp))
-	  (var-list (caddr exp))
-	  (body (cadddr exp)))
-      `(,%receive (params rest-args)
-	   (,%typed-optionals (,%list ,@(map cadr var-list)) ,args)
-         (,%if (pair? rest-args)
-	       (,%error "optionals: too many arguments and/or argument type mismatch"
-			rest-args)
-	       (,%let (,@(let loop ((counter 0)
-				    (var-list var-list))
-			   (if (null? var-list)
-			       '()
-			       (cons (cons (caar var-list) `((,%list-ref params ,counter)))
-				     (loop (+ 1 counter)
-					   (cdr var-list))))))
-		      ,body))))))
-
+  (syntax-rules ()
+    ((optionals args ((name  pred) ...) body)
+     (receive (params must-be-empty)
+	 (typed-optionals (list pred ...) args)
+       (apply (lambda (name ...) body) params)))))