diff --git a/redo/common_darwin.go b/redo/common_darwin.go
new file mode 100644
index 0000000..0c49a58
--- /dev/null
+++ b/redo/common_darwin.go
@@ -0,0 +1,13 @@
+// 20 july 2014
+
+package ui
+
+// #include "objc_darwin.h"
+import "C"
+
+func toBOOL(b bool) C.BOOL {
+	if b == true {
+		return C.YES
+	}
+	return C.NO
+}
diff --git a/redo/controls_darwin.go b/redo/controls_darwin.go
index 3c3289e..92eb836 100644
--- a/redo/controls_darwin.go
+++ b/redo/controls_darwin.go
@@ -9,14 +9,6 @@ import (
 // #include "objc_darwin.h"
 import "C"
 
-// TODO move to common_darwin.go
-func toBOOL(b bool) C.BOOL {
-	if b == true {
-		return C.YES
-	}
-	return C.NO
-}
-
 type widgetbase struct {
 	id		C.id
 	parentw	*window