From dda91f0e00b10e92a2dcefbe48baf2542d34dbe6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ion=20Gazta=C3=B1aga?= <igaztanaga@gmail.com>
Date: Fri, 18 Sep 2015 14:30:15 +0200
Subject: [PATCH] Return tree_iterator reference in tree traversal functions to
 allow easy chaining (e.g. i.go_parent().go_left().go_right())

---
 .../boost/intrusive/detail/tree_iterator.hpp  | 21 +++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/include/boost/intrusive/detail/tree_iterator.hpp b/include/boost/intrusive/detail/tree_iterator.hpp
index c2e980d..4985c6c 100644
--- a/include/boost/intrusive/detail/tree_iterator.hpp
+++ b/include/boost/intrusive/detail/tree_iterator.hpp
@@ -106,14 +106,23 @@ class tree_iterator
       return result;
    }
 
-   void go_left()
-   { members_.nodeptr_ = node_traits::get_left(members_.nodeptr_); }
+   tree_iterator&  go_left()
+   {
+      members_.nodeptr_ = node_traits::get_left(members_.nodeptr_);
+      return static_cast<tree_iterator&> (*this);
+   }
 
-   void go_right()
-   { members_.nodeptr_ = node_traits::get_right(members_.nodeptr_); }
+   tree_iterator&  go_right()
+   {
+      members_.nodeptr_ = node_traits::get_right(members_.nodeptr_);
+      return static_cast<tree_iterator&> (*this);
+   }
 
-   void go_parent()
-   { members_.nodeptr_ = node_traits::get_parent(members_.nodeptr_); }
+   tree_iterator&  go_parent()
+   {
+      members_.nodeptr_ = node_traits::get_parent(members_.nodeptr_);
+      return static_cast<tree_iterator&> (*this);
+   }
 
    operator unspecified_bool_type() const
    {  return members_.nodeptr_ ? &tree_iterator::unspecified_bool_type_func : 0;   }