1 /**************************************************************************** 2 ** 3 ** Copyright (C) 2016 The Qt Company Ltd. 4 ** Contact: https://www.qt.io/licensing/ 5 ** 6 ** This file is part of the QtXmlPatterns module of the Qt Toolkit. 7 ** 8 ** $QT_BEGIN_LICENSE:LGPL$ 9 ** Commercial License Usage 10 ** Licensees holding valid commercial Qt licenses may use this file in 11 ** accordance with the commercial license agreement provided with the 12 ** Software or, alternatively, in accordance with the terms contained in 13 ** a written agreement between you and The Qt Company. For licensing terms 14 ** and conditions see https://www.qt.io/terms-conditions. For further 15 ** information use the contact form at https://www.qt.io/contact-us. 16 ** 17 ** GNU Lesser General Public License Usage 18 ** Alternatively, this file may be used under the terms of the GNU Lesser 19 ** General Public License version 3 as published by the Free Software 20 ** Foundation and appearing in the file LICENSE.LGPL3 included in the 21 ** packaging of this file. Please review the following information to 22 ** ensure the GNU Lesser General Public License version 3 requirements 23 ** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. 24 ** 25 ** GNU General Public License Usage 26 ** Alternatively, this file may be used under the terms of the GNU 27 ** General Public License version 2.0 or (at your option) the GNU General 28 ** Public license version 3 or any later version approved by the KDE Free 29 ** Qt Foundation. The licenses are as published by the Free Software 30 ** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 31 ** included in the packaging of this file. Please review the following 32 ** information to ensure the GNU General Public License requirements will 33 ** be met: https://www.gnu.org/licenses/gpl-2.0.html and 34 ** https://www.gnu.org/licenses/gpl-3.0.html. 35 ** 36 ** $QT_END_LICENSE$ 37 ** 38 ****************************************************************************/ 39 40 // 41 // W A R N I N G 42 // ------------- 43 // 44 // This file is not part of the Qt API. It exists purely as an 45 // implementation detail. This header file may change from version to 46 // version without notice, or even be removed. 47 // 48 // We mean it. 49 50 #ifndef Patternist_ValueComparison_H 51 #define Patternist_ValueComparison_H 52 53 #include <private/qatomiccomparator_p.h> 54 #include <private/qpaircontainer_p.h> 55 #include <private/qcomparisonplatform_p.h> 56 57 QT_BEGIN_NAMESPACE 58 59 namespace QPatternist 60 { 61 62 /** 63 * @short Implements XPath 2.0 value comparions, such as the <tt>eq</tt> operator. 64 * 65 * ComparisonPlatform is inherited with @c protected scope because ComparisonPlatform 66 * must access members of ValueComparison. 67 * 68 * @see <a href="http://www.w3.org/TR/xpath20/#id-value-comparisons">XML Path Language 69 * (XPath) 2.0, 3.5.1 Value Comparisons</a> 70 * @author Frans Englich <frans.englich@nokia.com> 71 * @ingroup Patternist_expressions 72 */ 73 class Q_AUTOTEST_EXPORT ValueComparison 74 : public PairContainer, public ComparisonPlatform<ValueComparison, true> 75 { 76 public: 77 ValueComparison(const Expression::Ptr &op1, 78 const AtomicComparator::Operator op, 79 const Expression::Ptr &op2); 80 ~ValueComparison(); 81 82 virtual Item evaluateSingleton(const DynamicContext::Ptr &) const; 83 84 virtual Expression::Ptr typeCheck(const StaticContext::Ptr &context, 85 const SequenceType::Ptr &reqType); 86 87 /** 88 * @returns always CommonSequenceTypes::ExactlyOneBoolean 89 */ 90 virtual SequenceType::Ptr staticType() const; 91 92 virtual SequenceType::List expectedOperandTypes() const; 93 94 /** 95 * @returns IDValueComparison 96 */ 97 virtual ID id() const; 98 99 virtual ExpressionVisitorResult::Ptr accept(const ExpressionVisitor::Ptr &visitor) const; 100 virtual QList<QExplicitlySharedDataPointer<OptimizationPass> > optimizationPasses() const; 101 102 /** 103 * Overridden to optimize case-insensitive compares. 104 */ 105 virtual Expression::Ptr compress(const StaticContext::Ptr &context); 106 107 /** 108 * @returns the operator that this ValueComparison is using. 109 */ operatorID()110 inline AtomicComparator::Operator operatorID() const 111 { 112 return m_operator; 113 } 114 115 /** 116 * It is considered that the string value from @p op1 will be compared against @p op2. This 117 * function determines whether the user intends the comparison to be case insensitive. If 118 * that is the case @c true is returned, and the operands are re-written appropriately. 119 * 120 * This is a helper function for Expression classes that compares strings. 121 * 122 * @see ComparisonPlatform::useCaseInsensitiveComparator() 123 */ 124 static bool isCaseInsensitiveCompare(Expression::Ptr &op1, Expression::Ptr &op2); 125 126 private: 127 const AtomicComparator::Operator m_operator; 128 }; 129 } 130 131 QT_END_NAMESPACE 132 133 #endif 134