Refactor the module structure

private/utils.rkt

@@ -0,0 +1,80 @@
+(module utils racket/base
+
+  (require racket/path
+           racket/runtime-path
+           ffi/unsafe
+           setup/dirs
+           )
+  
+  (provide while
+           until
+           build-lib-path
+           get-lib
+           do-for
+           )
+
+  (define-syntax while
+    (syntax-rules ()
+      ((_ cond body ...)
+       (letrec ((while-f (lambda (last-result)
+                           (if cond
+                               (let ((last-result (begin
+                                                    body
+                                                    ...)))
+                                 (while-f last-result))
+                               last-result))))
+         (while-f #f))
+       )
+      ))
+
+  (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-runtime-path lib-path "..")
+
+  (define (build-lib-path)
+    (let ((os-type (system-type 'os*)))
+      (if (eq? os-type 'windows)
+          (build-path lib-path "lib" "dll")
+          (let* ((arch (symbol->string (system-type 'arch)))
+                 (subdir (string-append (symbol->string os-type) "-" arch)))
+            (let ((path (build-path lib-path "lib" subdir)))
+              path)))))
+
+  (define (get-lib* libs-to-try orig-libs versions)
+    (if (null? libs-to-try)
+        (error (format "Cannot find library, tried ~a" orig-libs)) 
+        (ffi-lib (car libs-to-try) versions
+                 #:get-lib-dirs (λ () (cons (build-lib-path) (get-lib-search-dirs)))
+                 #:fail (λ () (get-lib* (cdr libs-to-try) orig-libs versions))
+                 )))
+
+  (define (get-lib libs-to-try versions)
+    (get-lib* libs-to-try libs-to-try versions))
+  
+  ) ; end of module