diff --git a/include/extra/array.h b/include/extra/array.h
index 8cc7c9a..6ec3825 100644
--- a/include/extra/array.h
+++ b/include/extra/array.h
@@ -12,7 +12,9 @@
 
 extern ssize_t libcdsb_array_get(vtype_value* x, vtype_array* s, ssize_t index, _Bool cut) LIBCDSB_nt__ LIBCDSB_nn2__;
 
-extern ssize_t libcdsb_array_find(const vtype_array* x, const void* value, vtype value_type)  LIBCDSB_nt__ LIBCDSB_nn1__;
-extern ssize_t libcdsb_array_push(      vtype_array* x, const void* value, vtype value_type)  LIBCDSB_nt__ LIBCDSB_nn1__;
+extern ssize_t libcdsb_array_find(const vtype_array* x, const void* value, vtype value_type) LIBCDSB_nt__ LIBCDSB_nn1__;
+extern ssize_t libcdsb_array_push(      vtype_array* x, const void* value, vtype value_type) LIBCDSB_nt__ LIBCDSB_nn1__;
+
+extern int array_foreach(vtype_array* x, int (*callback)(void* value, ssize_t index, vtype type)) LIBCDSB_nt__ LIBCDSB_nn12__;
 
 #endif /* LIBCDSB_EXTRA_ARRAY_H */
diff --git a/include/extra/list.h b/include/extra/list.h
index d62b3eb..68f1168 100644
--- a/include/extra/list.h
+++ b/include/extra/list.h
@@ -11,13 +11,13 @@
 #define list_pop_by_index(x, s, index) libcdsb_list_get(x, s, index, 1)
 #define list_remove_by_index(s, index) libcdsb_list_get(0, s, index, 1)
 
-extern ssize_t libcdsb_list_find  (vtype_value* x, vtype_list* s, const void* value, vtype type, _Bool reverse, _Bool cut);
-extern _Bool   libcdsb_list_update(vtype_list*  x, ssize_t index, const void* value, vtype type, int ins_direction);
+extern ssize_t libcdsb_list_find  (vtype_value* x, vtype_list* s, const void* value, vtype type, _Bool reverse, _Bool cut) LIBCDSB_nt__ LIBCDSB_nn2__;
+extern _Bool   libcdsb_list_update(vtype_list*  x, ssize_t index, const void* value, vtype type, int ins_direction) LIBCDSB_nt__ LIBCDSB_nn1__;
 
-extern size_t  libcdsb_list_count(const vtype_list* s, const void* value, vtype type);
+extern size_t  libcdsb_list_count(const vtype_list* s, const void* value, vtype type) LIBCDSB_nt__ LIBCDSB_nn1__;
 
-extern ssize_t libcdsb_list_get(vtype_value* x, vtype_list* s, ssize_t index, _Bool cut);
+extern ssize_t libcdsb_list_get(vtype_value* x, vtype_list* s, ssize_t index, _Bool cut) LIBCDSB_nt__ LIBCDSB_nn2__;
 
-extern int list_foreach(const vtype_list* x, int (*callback)(void* value, ssize_t index, vtype type));
+extern int list_foreach(const vtype_list* x, int (*callback)(void* value, ssize_t index, vtype type)) LIBCDSB_nt__ LIBCDSB_nn12__;
 
 #endif /* LIBCDSB_EXTRA_LIST_H */
diff --git a/include/list.h b/include/list.h
index 7e1aece..eda1488 100644
--- a/include/list.h
+++ b/include/list.h
@@ -18,7 +18,7 @@ extern void list_reverse(vtype_list* x);
 #define list_pop(x, s, value)   _LIBCDSB_Generic(libcdsb_list, find, value)(x, s, value, 0, 1)
 #define list_find(x, s, value)  _LIBCDSB_Generic(libcdsb_list, find, value)(x, s, value, 0, 0)
 #define list_rfind(x, s, value) _LIBCDSB_Generic(libcdsb_list, find, value)(x, s, value, 1, 0)
-#define list_countof(s, value)  _LIBCDSB_Generic(libcdsb_list, count, value)(x, value)
+#define list_countof(s, value)  _LIBCDSB_Generic(libcdsb_list, count, value)(s, value)
 #define list_indexof(s, value)  list_find(0, s, value)
 #define list_remove(s, value)   list_pop(0, s, value)
 #define in_list(s, value)       (list_indexof(s, value) >= 0)
diff --git a/src/array/extra.c b/src/array/extra.c
index 3baefbb..25b1d2c 100644
--- a/src/array/extra.c
+++ b/src/array/extra.c
@@ -73,3 +73,27 @@ ssize_t libcdsb_array_get(val_t* x, arr_t* s, ssize_t i, _Bool cut) {
 
     return i;
 }
+
+/*#####################################################################################################################*/
+
+int array_foreach(vtype_array* x, int (*callback)(void* value, ssize_t index, vtype type)) {
+
+    void*  p;
+    void*  e;
+    size_t n;
+    int    r;
+
+    p = x->mem;
+    e = x->mem + x->size*vtype_size(x->type);
+    n = 0;
+
+    while (p < e) {
+        if ((r = callback(p, n, x->type)))
+            return r;
+
+        p += vtype_size(x->type);
+        ++n;
+    }
+
+    return 0;
+}