1 /* 2 * Copyright (C) 2008 Apple Inc. All Rights Reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR 17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #ifndef NodeWithIndex_h 27 #define NodeWithIndex_h 28 29 #include "core/dom/Node.h" 30 31 namespace WebCore { 32 33 // For use when you want to get the index for a node repeatedly and 34 // only want to walk the child list to figure out the index once. 35 class NodeWithIndex { 36 public: 37 explicit NodeWithIndex(Node& node) 38 : m_node(node) 39 , m_index(-1) 40 { 41 } 42 43 Node& node() const { return m_node; } 44 45 int index() const 46 { 47 if (!hasIndex()) 48 m_index = m_node.nodeIndex(); 49 ASSERT(hasIndex()); 50 ASSERT(m_index == static_cast<int>(m_node.nodeIndex())); 51 return m_index; 52 } 53 54 private: 55 bool hasIndex() const { return m_index >= 0; } 56 57 Node& m_node; 58 mutable int m_index; 59 }; 60 61 } 62 63 #endif 64
