data tree FEATURE use hashes of data nodes to be able to compare them effectively
diff --git a/src/tree_data_internal.h b/src/tree_data_internal.h
index 75ef8f3..5adeac9 100644
--- a/src/tree_data_internal.h
+++ b/src/tree_data_internal.h
@@ -76,6 +76,22 @@
*/
/**
+ * @brief Generate hash for the node.
+ *
+ * @param[in] node Data node to (re)generate hash value.
+ * @return LY_ERR value.
+ */
+LY_ERR lyd_hash(struct lyd_node *node);
+
+/**
+ * @brief Insert hash of the node into the hash table of its parent.
+ *
+ * @param[in] node Data node which hash will be inserted into the lyd_node_inner::children_hash hash table of its parent.
+ * @return LY_ERR value.
+ */
+LY_ERR lyd_insert_hash(struct lyd_node *node);
+
+/**
* @brief Maintain node's parent's children hash table when unlinking the node.
*
* When completely freeing data tree, it is expected to free the parent's children hash table first, at once.