From d1c6e186bfad1599c9605ff3b39e66b06f920cd5 Mon Sep 17 00:00:00 2001
From: "Brian J. Burg" <burg@cs.washington.edu>
Date: Sat, 13 Oct 2012 18:13:44 -0700
Subject: [PATCH] Add some helper methods to util::tree for accessing tree
 fields (it wasn't possible before due to multiple with_tree_fields
 implementations)

---
 src/servo/util/tree.rs | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/src/servo/util/tree.rs b/src/servo/util/tree.rs
index 1436a92707e..2f58c8c4d56 100644
--- a/src/servo/util/tree.rs
+++ b/src/servo/util/tree.rs
@@ -34,6 +34,26 @@ pub fn each_child<T:Copy,O:ReadMethods<T>>(ops: &O, node: &T, f: fn(&T) -> bool)
     }
 }
 
+pub fn first_child<T:Copy,O:ReadMethods<T>>(ops: &O, node: &T) -> Option<T> {
+    ops.with_tree_fields(node, |tf| tf.first_child)
+}
+
+pub fn last_child<T:Copy,O:ReadMethods<T>>(ops: &O, node: &T) -> Option<T> {
+    ops.with_tree_fields(node, |tf| tf.last_child)
+}
+
+pub fn next_sibling<T:Copy,O:ReadMethods<T>>(ops: &O, node: &T) -> Option<T> {
+    ops.with_tree_fields(node, |tf| tf.next_sibling)
+}
+
+pub fn prev_sibling<T:Copy,O:ReadMethods<T>>(ops: &O, node: &T) -> Option<T> {
+    ops.with_tree_fields(node, |tf| tf.prev_sibling)
+}
+
+pub fn parent<T:Copy,O:ReadMethods<T>>(ops: &O, node: &T) -> Option<T> {
+    ops.with_tree_fields(node, |tf| tf.parent)
+}
+
 pub fn empty<T>() -> Tree<T> {
     {mut parent: None,
      mut first_child: None,