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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_LetClause_H
53 #define Patternist_LetClause_H
55 #include <private/qpaircontainer_p.h>
56 #include <private/qvariabledeclaration_p.h>
66 * @short Represents a <tt>let</tt>-clause, but is only used at compile
69 * LetClause is inserted into the AST tree for the single purpose of
70 * ensuring that the focus is correct for the binding expression. Once
71 * that is done, LetClause sometimes rewrites itself to its
72 * <tt>return</tt> expression, and the ExpressionVariableReference will
73 * handle the evaluation of the variable.
75 * @author Frans Englich <frans.englich@nokia.com>
76 * @ingroup Patternist_expressions
78 class LetClause : public PairContainer
81 LetClause(const Expression::Ptr &operand1,
82 const Expression::Ptr &operand2,
83 const VariableDeclaration::Ptr &decl);
85 virtual Item::Iterator::Ptr evaluateSequence(const DynamicContext::Ptr &context) const;
86 virtual Item evaluateSingleton(const DynamicContext::Ptr &context) const;
87 virtual bool evaluateEBV(const DynamicContext::Ptr &context) const;
88 virtual void evaluateToSequenceReceiver(const DynamicContext::Ptr &context) const;
90 virtual SequenceType::List expectedOperandTypes() const;
91 virtual Expression::Ptr typeCheck(const StaticContext::Ptr &context,
92 const SequenceType::Ptr &reqType);
93 virtual SequenceType::Ptr staticType() const;
94 virtual Properties properties() const;
95 virtual ExpressionVisitorResult::Ptr accept(const ExpressionVisitor::Ptr &visitor) const;
96 virtual ID id() const;
99 inline DynamicContext::Ptr bindVariable(const DynamicContext::Ptr &context) const;
101 const VariableDeclaration::Ptr m_varDecl;