diff --git a/core/include/blue/core/iterator.h b/core/include/blue/core/iterator.h
index 16ce7a8..f294465 100644
--- a/core/include/blue/core/iterator.h
+++ b/core/include/blue/core/iterator.h
@@ -9,9 +9,26 @@
 B_DECLS_BEGIN;
 
 #define b_foreach(type, var, iterator)                                         \
-	for (type var = (type)b_iterator_value(iterator).v_int; var != NULL;   \
-	     b_iterator_next(iterator),                                        \
-	          var = (type)b_iterator_value(iterator).v_int)
+	for (type var = (type)b_iterator_get_value(iterator).v_int;            \
+	     B_OK(b_iterator_get_status(iterator));                            \
+	     b_iterator_move_next(iterator),                                   \
+	          var = (type)b_iterator_get_value(iterator).v_int)
+#define b_foreach_ptr(type, var, iterator)                                     \
+	for (type *var = (type *)b_iterator_get_value(iterator).v_ptr;         \
+	     B_OK(b_iterator_get_status(iterator));                            \
+	     b_iterator_move_next(iterator),                                   \
+	          var = (type *)b_iterator_get_value(iterator).v_ptr)
+#define b_foreach_c(type, var, iterator)                                       \
+	for (type var = (type)b_iterator_get_cvalue(iterator).v_int;           \
+	     B_OK(b_iterator_get_status(iterator));                            \
+	     b_iterator_move_next(iterator),                                   \
+	          var = (type)b_iterator_get_cvalue(iterator).v_int)
+#define b_foreach_cptr(type, var, iterator)                                    \
+	for (const type *var                                                   \
+	     = (const type *)b_iterator_get_cvalue(iterator).v_cptr;           \
+	     B_OK(b_iterator_get_status(iterator));                            \
+	     b_iterator_move_next(iterator),                                   \
+	     var = (const type *)b_iterator_get_cvalue(iterator).v_cptr)
 
 #define B_ITERATOR_VALUE_INT(v)     ((b_iterator_value) {.v_int = (v)})
 #define B_ITERATOR_VALUE_PTR(v)     ((b_iterator_value) {.v_ptr = (v)})
@@ -28,7 +45,8 @@ typedef union b_iterator_value {
 	const void *v_cptr;
 } b_iterator_value;
 
-B_DECLARE_TYPE(b_iterator);
+__B_DECLARE_TYPE(b_iterator);
+
 B_DECLARE_TYPE(b_iterable);
 
 B_TYPE_CLASS_DECLARATION_BEGIN(b_iterator)
@@ -46,13 +64,22 @@ B_TYPE_CLASS_DECLARATION_END(b_iterable)
 BLUE_API b_type b_iterator_get_type(void);
 BLUE_API b_type b_iterable_get_type(void);
 
+static inline const b_iterator *b_iterator_ref(const b_iterator *p)
+{
+	return b_object_ref((b_object *)p);
+}
+static inline void b_iterator_unref(const b_iterator *p)
+{
+	b_object_unref((b_object *)p);
+}
+
 BLUE_API b_iterator *b_iterator_begin(b_iterable *it);
 BLUE_API const b_iterator *b_iterator_cbegin(const b_iterable *it);
 
 BLUE_API b_status b_iterator_get_status(const b_iterator *it);
 BLUE_API b_status b_iterator_set_status(const b_iterator *it, b_status status);
 
-BLUE_API b_status b_iterator_next(const b_iterator *it);
+BLUE_API b_status b_iterator_move_next(const b_iterator *it);
 BLUE_API b_iterator_value b_iterator_get_value(b_iterator *it);
 BLUE_API const b_iterator_value b_iterator_get_cvalue(const b_iterator *it);
 BLUE_API b_status b_iterator_erase(b_iterator *it);
diff --git a/core/include/blue/core/macros.h b/core/include/blue/core/macros.h
index 380836c..5f426d0 100644
--- a/core/include/blue/core/macros.h
+++ b/core/include/blue/core/macros.h
@@ -92,9 +92,12 @@
 
 /* Type declaration macros (for use in .h header file) */
 
-#define B_DECLARE_TYPE(name)                                                   \
+#define __B_DECLARE_TYPE(name)                                                 \
 	typedef B_TYPE_FWDREF(name) name;                                      \
-	typedef struct _##name##_class name##_class;                           \
+	typedef struct _##name##_class name##_class;
+
+#define B_DECLARE_TYPE(name)                                                   \
+	__B_DECLARE_TYPE(name);                                                \
 	static inline name *name##_ref(name *p)                                \
 	{                                                                      \
 		return b_object_ref(p);                                        \
diff --git a/core/iterator.c b/core/iterator.c
index a365a7c..d311fe8 100644
--- a/core/iterator.c
+++ b/core/iterator.c
@@ -41,10 +41,19 @@ enum b_status b_iterator_set_status(const b_iterator *it, b_status status)
 	B_CLASS_DISPATCH_STATIC(B_TYPE_ITERATOR, iterator_set_status, it, status);
 }
 
-b_status b_iterator_move_next(b_iterator *it)
+enum b_status b_iterator_move_next(const b_iterator *it)
 {
-	B_CLASS_DISPATCH_VIRTUAL_0(
-		b_iterator, B_TYPE_ITERATOR, B_ERR_NOT_SUPPORTED, it_move_next, it);
+	enum b_status status = B_ERR_NOT_SUPPORTED;
+
+	b_iterator_class *iface = b_object_get_interface(it, B_TYPE_ITERATOR);
+	if (iface && iface->it_move_next) {
+		status = iface->it_move_next(it);
+	}
+
+	struct b_iterator_p *p = b_object_get_private(it, B_TYPE_ITERATOR);
+	p->it_status = status;
+
+	return status;
 }
 
 b_iterator_value b_iterator_get_value(b_iterator *it)
@@ -63,8 +72,17 @@ const b_iterator_value b_iterator_get_cvalue(const b_iterator *it)
 
 b_status b_iterator_erase(b_iterator *it)
 {
-	B_CLASS_DISPATCH_VIRTUAL_0(
-		b_iterator, B_TYPE_ITERATOR, B_ERR_NOT_SUPPORTED, it_erase, it);
+	enum b_status status = B_ERR_NOT_SUPPORTED;
+
+	b_iterator_class *iface = b_object_get_interface(it, B_TYPE_ITERATOR);
+	if (iface && iface->it_erase) {
+		status = iface->it_erase(it);
+	}
+
+	struct b_iterator_p *p = b_object_get_private(it, B_TYPE_ITERATOR);
+	p->it_status = status;
+
+	return status;
 }
 
 /*** CLASS DEFINITION *********************************************************/