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 "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 NodeWithIndex(Node* node) 38 : m_node(node) 39 , m_haveIndex(false) 40 { 41 ASSERT(node); 42 } 43 44 Node* node() const { return m_node; } 45 46 int index() const 47 { 48 if (!m_haveIndex) { 49 m_index = m_node->nodeIndex(); 50 m_haveIndex = true; 51 } 52 ASSERT(m_index == static_cast<int>(m_node->nodeIndex())); 53 return m_index; 54 } 55 56 private: 57 Node* m_node; 58 mutable bool m_haveIndex; 59 mutable int m_index; 60 }; 61 62 } 63 64 #endif 65
