1/* 2 * Copyright (C) 2005 Frerich Raabe <raabe@kde.org> 3 * Copyright (C) 2006, 2009 Apple Inc. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27#ifndef XPathExpressionNode_h 28#define XPathExpressionNode_h 29 30#include "Node.h" 31#include "XPathValue.h" 32#include <wtf/HashMap.h> 33#include <wtf/Vector.h> 34#include <wtf/text/StringHash.h> 35 36namespace WebCore { 37 38 namespace XPath { 39 40 struct EvaluationContext { 41 WTF_MAKE_FAST_ALLOCATED; 42 public: 43 RefPtr<Node> node; 44 unsigned long size; 45 unsigned long position; 46 HashMap<String, String> variableBindings; 47 48 bool hadTypeConversionError; 49 }; 50 51 class ParseNode { 52 public: 53 virtual ~ParseNode() { } 54 }; 55 56 class Expression : public ParseNode { 57 WTF_MAKE_NONCOPYABLE(Expression); WTF_MAKE_FAST_ALLOCATED; 58 public: 59 static EvaluationContext& evaluationContext(); 60 61 Expression(); 62 virtual ~Expression(); 63 64 virtual Value evaluate() const = 0; 65 66 void addSubExpression(Expression* expr) 67 { 68 m_subExpressions.append(expr); 69 m_isContextNodeSensitive |= expr->m_isContextNodeSensitive; 70 m_isContextPositionSensitive |= expr->m_isContextPositionSensitive; 71 m_isContextSizeSensitive |= expr->m_isContextSizeSensitive; 72 } 73 74 bool isContextNodeSensitive() const { return m_isContextNodeSensitive; } 75 bool isContextPositionSensitive() const { return m_isContextPositionSensitive; } 76 bool isContextSizeSensitive() const { return m_isContextSizeSensitive; } 77 void setIsContextNodeSensitive(bool value) { m_isContextNodeSensitive = value; } 78 void setIsContextPositionSensitive(bool value) { m_isContextPositionSensitive = value; } 79 void setIsContextSizeSensitive(bool value) { m_isContextSizeSensitive = value; } 80 81 virtual Value::Type resultType() const = 0; 82 83 protected: 84 unsigned subExprCount() const { return m_subExpressions.size(); } 85 Expression* subExpr(unsigned i) { return m_subExpressions[i]; } 86 const Expression* subExpr(unsigned i) const { return m_subExpressions[i]; } 87 88 private: 89 Vector<Expression*> m_subExpressions; 90 91 // Evaluation details that can be used for optimization. 92 bool m_isContextNodeSensitive; 93 bool m_isContextPositionSensitive; 94 bool m_isContextSizeSensitive; 95 }; 96 97 } 98 99} 100 101#endif // EXPRESSION_H 102