From e7d45749ffd0811a3bc7e28919e2ecf5eeb853af Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Vytautas=20=C5=A0altenis?= <vytas@rtfb.lt>
Date: Tue, 5 Apr 2016 10:08:50 +0300
Subject: [PATCH] Give node visitor callback type a name and docs

---
 node.go | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/node.go b/node.go
index 9bb2df4..c565d5c 100644
--- a/node.go
+++ b/node.go
@@ -230,7 +230,12 @@ func (n *Node) canContain(t NodeType) bool {
 	return false
 }
 
-func (root *Node) Walk(visitor func(node *Node, entering bool)) {
+// NodeVisitor is a callback to be called when traversing the syntax tree.
+// Called twice for every node: once with entering=true when the branch is
+// first visited, then with entering=false after all the children are done.
+type NodeVisitor func(node *Node, entering bool)
+
+func (root *Node) Walk(visitor NodeVisitor) {
 	walker := NewNodeWalker(root)
 	node, entering := walker.next()
 	for node != nil {