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46 // This file is not part of the Qt API. It exists purely as an
47 // implementation detail. This header file may change from version to
48 // version without notice, or even be removed.
52 #ifndef Patternist_Literal_H
53 #define Patternist_Literal_H
55 #include <private/qemptycontainer_p.h>
64 * @short Houses an AtomicValue, making it available as an Expression.
66 * This is not only literals that can be created via the XQuery syntax(strings and numbers), but
67 * all other atomic values, such as <tt>xs:date</tt> or <tt>xs:time</tt>.
69 * @see <a href="http://www.w3.org/TR/xquery/#id-literals">XQuery 1.0: An XML Query Language,
71 * @author Frans Englich <frans.englich@nokia.com>
72 * @ingroup Patternist_expressions
74 class Literal : public EmptyContainer
78 * Creates a Literal that represents @p item.
80 * @param item must be non-null and cannot be a QXmlNodeModelIndex.
82 Literal(const Item &item);
84 virtual Item evaluateSingleton(const DynamicContext::Ptr &context) const;
85 virtual bool evaluateEBV(const DynamicContext::Ptr &context) const;
86 void evaluateToSequenceReceiver(const DynamicContext::Ptr &context) const;
88 virtual SequenceType::Ptr staticType() const;
89 virtual ExpressionVisitorResult::Ptr accept(const ExpressionVisitor::Ptr &visitor) const;
90 virtual ID id() const;
91 virtual QString description() const;
94 * @returns Expression::DisableElimination and Expression::IsEvaluated
96 virtual Properties properties() const;
99 * Declaring the return value of this function a const reference, leads
100 * to crashes in patternistview, for a to me unknown reason.
102 inline Item item() const
112 * @short Creates a Literal that wraps @p item, and returns it.
114 * This simplifies code. Instead of writing:
117 * Expression::Ptr(new Literal(item));
126 * This function is not declared static, because it breaks the build on
127 * at least aix-xlc-64.
131 inline Expression::Ptr wrapLiteral(const Item &item,
132 const StaticContext::Ptr &context,
133 const SourceLocationReflection *const r)
137 const Expression::Ptr retval(new Literal(item));
138 context->addLocation(retval.data(), context->locationFor(r));