Make NewCommonAttributes public

id.go

@@ -15,7 +15,7 @@ type ID struct {
 // NewID creates a new ID. It returns a *ID.
 func NewID(uri string) *ID {
 	return &ID{
-		CommonAttributes: newCommonAttributes(),
+		CommonAttributes: NewCommonAttributes(),
 		URI:              uri,
 	}
 }