diff --git a/core/include/blue/core/macros.h b/core/include/blue/core/macros.h
index ee9beb9..3e5a42d 100644
--- a/core/include/blue/core/macros.h
+++ b/core/include/blue/core/macros.h
@@ -111,16 +111,16 @@
 
 #define B_CLASS_DISPATCH_VIRTUAL(type_name, type_id, object, func, ...)        \
 	do {                                                                   \
-		type_name##_class *iface = b_object_get_interface(             \
-			object, type_name##_class, type_id);                   \
+		type_name##_class *iface                                       \
+			= b_object_get_interface(object, type_id);             \
 		if (iface && iface->func) {                                    \
 			return iface->func(__VA_ARGS__);                       \
 		}                                                              \
 	} while (0)
 #define B_CLASS_DISPATCH_VIRTUAL_V(type_name, type_id, object, func, ...)      \
 	do {                                                                   \
-		type_name##_class *iface = b_object_get_interface(             \
-			object, type_name##_class, type_id);                   \
+		type_name##_class *iface                                       \
+			= b_object_get_interface(object, type_id);             \
 		if (iface && iface->func) {                                    \
 			iface->func(__VA_ARGS__);                              \
 			return;                                                \
diff --git a/core/include/blue/core/object.h b/core/include/blue/core/object.h
index 2a929be..fedf1c3 100644
--- a/core/include/blue/core/object.h
+++ b/core/include/blue/core/object.h
@@ -18,19 +18,11 @@ typedef struct _b_object_class {
 	void (*to_string)(b_object *, struct b_stream *);
 } b_object_class;
 
-#define b_object_get_private(object, private_struct, type_id)                  \
-	((private_struct *)z__b_object_get_private(B_OBJECT(object), type_id));
-#define b_object_get_protected(object, protected_struct, type_id)              \
-	((protected_struct *)z__b_object_get_protected(B_OBJECT(object), type_id));
-#define b_object_get_interface(object, interface_struct, interface_id)         \
-	((interface_struct *)z__b_object_get_interface(                        \
-		B_OBJECT(object), interface_id));
-
 BLUE_API b_type b_object_get_type(void);
 
-BLUE_API void *z__b_object_get_private(b_object *object, b_type type);
-BLUE_API void *z__b_object_get_protected(b_object *object, b_type type);
-BLUE_API void *z__b_object_get_interface(b_object *object, b_type type);
+BLUE_API void *b_object_get_private(b_object *object, b_type type);
+BLUE_API void *b_object_get_protected(b_object *object, b_type type);
+BLUE_API void *b_object_get_interface(b_object *object, b_type type);
 
 b_object *b_retain(b_object *p);
 BLUE_API void b_release(b_object *p);
diff --git a/core/object.c b/core/object.c
index 29d8385..5e06dac 100644
--- a/core/object.c
+++ b/core/object.c
@@ -77,7 +77,7 @@ void b_object_to_string(struct _b_object *p, struct b_stream *out)
 	b_stream_write_fmt(out, NULL, "<%s@%p>", p->obj_type->r_info->t_name, p);
 }
 
-void *z__b_object_get_private(struct _b_object *object, b_type type)
+void *b_object_get_private(struct _b_object *object, b_type type)
 {
 	if (b_type_id_compare(&object->obj_type->r_info->t_id, type) == 0) {
 		return (char *)object + object->obj_main_priv_offset;
@@ -92,7 +92,7 @@ void *z__b_object_get_private(struct _b_object *object, b_type type)
 	return (char *)object + comp->c_instance_private_data_offset;
 }
 
-void *z__b_object_get_protected(struct _b_object *object, b_type type)
+void *b_object_get_protected(struct _b_object *object, b_type type)
 {
 	struct b_type_component *comp
 		= b_type_get_component(&object->obj_type->r_components, type);
@@ -103,7 +103,7 @@ void *z__b_object_get_protected(struct _b_object *object, b_type type)
 	return (char *)object + comp->c_instance_protected_data_offset;
 }
 
-void *z__b_object_get_interface(struct _b_object *object, b_type type)
+void *b_object_get_interface(struct _b_object *object, b_type type)
 {
 	return z__b_class_get_interface(object->obj_type->r_class, type);
 }