TreeWalker

DOM dom

Baseline: Widely available on the web, in every major browser since Jul 2015, and long enough to count on (since Jan 2018).

niso: No WPT tests. WPT maps no test to it. WPT results recorded at f3b4fa8, 2026-11-10; web-features 3.45.0. WPT tests · niso's support · Attr, CDATASection, CharacterData, Comment

TreeWalker is an interface in idl/dom.webidl, exposed in Window. What it does is on MDN; this page says what niso has of it.

Status

The web features its members belong to, each with its Baseline status on the web and how much of the feature’s WPT suite passes in niso (see Web platform support).

Feature	On the web	In niso	Members
DOM	Widely available	No WPT tests WPT maps no test to it	12

Members

root

attribute

[SameObject] readonly attribute Node root;

int32_t niso_tree_walker_get_root(niso_dom* dom, niso_handle self, niso_handle* out);

whatToShow

attribute

readonly attribute unsigned long whatToShow;

int32_t niso_tree_walker_get_what_to_show(niso_dom* dom, niso_handle self, uint32_t* out);

filter

attribute

readonly attribute NodeFilter? filter;

int32_t niso_tree_walker_get_filter(niso_dom* dom, niso_handle self, void** out);

currentNode

attribute

attribute Node currentNode;

int32_t niso_tree_walker_get_current_node(niso_dom* dom, niso_handle self, niso_handle* out);
int32_t niso_tree_walker_set_current_node(niso_dom* dom, niso_handle self, niso_handle value);

parentNode()

operation

[NisoReentrant] Node? parentNode();

int32_t niso_tree_walker_parent_node(niso_dom* dom, niso_handle self, niso_handle* out);

firstChild()

operation

[NisoReentrant] Node? firstChild();

int32_t niso_tree_walker_first_child(niso_dom* dom, niso_handle self, niso_handle* out);

lastChild()

operation

[NisoReentrant] Node? lastChild();

int32_t niso_tree_walker_last_child(niso_dom* dom, niso_handle self, niso_handle* out);

previousSibling()

operation

[NisoReentrant] Node? previousSibling();

int32_t niso_tree_walker_previous_sibling(niso_dom* dom, niso_handle self, niso_handle* out);

nextSibling()

operation

[NisoReentrant] Node? nextSibling();

int32_t niso_tree_walker_next_sibling(niso_dom* dom, niso_handle self, niso_handle* out);

previousNode()

operation

[NisoReentrant] Node? previousNode();

int32_t niso_tree_walker_previous_node(niso_dom* dom, niso_handle self, niso_handle* out);

nextNode()

operation

[NisoReentrant] Node? nextNode();

int32_t niso_tree_walker_next_node(niso_dom* dom, niso_handle self, niso_handle* out);