sound

utils/utils.rkt

@@ -1,7 +1,9 @@
 (module utils racket/base
 
   (provide while
+           until
            get-lib-path
+           do-for
            )
 
   (define-syntax while
@@ -18,12 +20,43 @@
        )
       ))
 
+  (define-syntax until
+    (syntax-rules ()
+      ((_ cond body ...)
+       (letrec ((until-f (lambda (last-result)
+                           (if cond
+                               last-result
+                               (let ((last-reult (begin
+                                                   body
+                                                   ...)))
+                                 (until-f last-result))))))
+         (until-f #f)))))
+
+  (define-syntax do-for
+    (syntax-rules ()
+      ((_ (init cond next) body ...)
+       (begin
+         init
+         (letrec ((do-for-f (lamba ()
+                                   (if cond
+                                       (begin
+                                         (begin
+                                           body
+                                           ...)
+                                         next
+                                         (do-for-f))))))
+           (do-for-f))))))
 
   (define (get-lib-path lib)
     (let ((platform (system-type)))
       (cond
         [(eq? platform 'windows) 
-         (build-path (current-directory) ".." "lib" "dll" lib)]
+         (let ((try1 (build-path (current-directory) ".." "lib" "dll" lib))
+               (try2 (build-path (current-directory) "lib" "dll" lib)))
+           (if (file-exists? try1)
+               try1
+               try2)
+           )]
         [else
          (error (format "Install the shared library: ~a" lib))]
         )))