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_Literal_H 51 #define Patternist_Literal_H 52 53 #include <private/qemptycontainer_p.h> 54 55 QT_BEGIN_NAMESPACE 56 57 namespace QPatternist 58 { 59 /** 60 * @short Houses an AtomicValue, making it available as an Expression. 61 * 62 * This is not only literals that can be created via the XQuery syntax(strings and numbers), but 63 * all other atomic values, such as <tt>xs:date</tt> or <tt>xs:time</tt>. 64 * 65 * @see <a href="http://www.w3.org/TR/xquery/#id-literals">XQuery 1.0: An XML Query Language, 66 * 3.1.1 Literals</a> 67 * @author Frans Englich <frans.englich@nokia.com> 68 * @ingroup Patternist_expressions 69 */ 70 class Literal : public EmptyContainer 71 { 72 public: 73 /** 74 * Creates a Literal that represents @p item. 75 * 76 * @param item must be non-null and cannot be a QXmlNodeModelIndex. 77 */ 78 Literal(const Item &item); 79 80 virtual Item evaluateSingleton(const DynamicContext::Ptr &context) const; 81 virtual bool evaluateEBV(const DynamicContext::Ptr &context) const; 82 void evaluateToSequenceReceiver(const DynamicContext::Ptr &context) const; 83 84 virtual SequenceType::Ptr staticType() const; 85 virtual ExpressionVisitorResult::Ptr accept(const ExpressionVisitor::Ptr &visitor) const; 86 virtual ID id() const; 87 virtual QString description() const; 88 89 /** 90 * @returns Expression::DisableElimination and Expression::IsEvaluated 91 */ 92 virtual Properties properties() const; 93 94 /** 95 * Declaring the return value of this function a const reference, leads 96 * to crashes in patternistview, for a to me unknown reason. 97 */ item()98 inline Item item() const 99 { 100 return m_item; 101 } 102 103 private: 104 const Item m_item; 105 }; 106 107 /** 108 * @short Creates a Literal that wraps @p item, and returns it. 109 * 110 * This simplifies code. Instead of writing: 111 * 112 * @code 113 * Expression::Ptr(new Literal(item)); 114 * @endcode 115 * 116 * One can write: 117 * 118 * @code 119 * wrapLiteral(item); 120 * @endcode 121 * 122 * This function is not declared static, because it breaks the build on 123 * at least aix-xlc-64. 124 * 125 * @relates Literal 126 */ wrapLiteral(const Item & item,const StaticContext::Ptr & context,const SourceLocationReflection * const r)127 inline Expression::Ptr wrapLiteral(const Item &item, 128 const StaticContext::Ptr &context, 129 const SourceLocationReflection *const r) 130 { 131 Q_ASSERT(item); 132 133 const Expression::Ptr retval(new Literal(item)); 134 context->addLocation(retval.data(), context->locationFor(r)); 135 136 return retval; 137 } 138 } 139 140 QT_END_NAMESPACE 141 142 #endif 143