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//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists purely as an
// implementation detail.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.

#ifndef Patternist_IfThenClause_H
#define Patternist_IfThenClause_H

#include "qtriplecontainer_p.h"

QT_BEGIN_HEADER

QT_BEGIN_NAMESPACE

namespace QPatternist
{
    /**
     * @short Implements XPath 2.0's conditional expression <tt>if([expr]) then [expr] else [expr]</tt>.
     *
     * @see <a href="http://www.w3.org/TR/xpath20/#id-conditionals">XML Path Language (XPath) 2.0,
     * 3.8 Conditional Expressions</a>
     * @author Frans Englich <frans.englich@nokia.com>
     * @ingroup Patternist_expressions
     */
    class IfThenClause : public TripleContainer
    {
    public:
        IfThenClause(const Expression::Ptr &test,
                     const Expression::Ptr &then,
                     const Expression::Ptr &el);

        virtual bool evaluateEBV(const DynamicContext::Ptr &context) const;
        virtual Item::Iterator::Ptr evaluateSequence(const DynamicContext::Ptr &context) const;
        virtual Item evaluateSingleton(const DynamicContext::Ptr &context) const;
        virtual void evaluateToSequenceReceiver(const DynamicContext::Ptr &context) const;

        virtual SequenceType::List expectedOperandTypes() const;
        virtual Expression::Ptr compress(const StaticContext::Ptr &context);

        virtual SequenceType::Ptr staticType() const;
        virtual ExpressionVisitorResult::Ptr accept(const ExpressionVisitor::Ptr &visitor) const;
        /**
         * @returns IDIfThenClause
         */
        virtual ID id() const;
        virtual QList<QExplicitlySharedDataPointer<OptimizationPass> > optimizationPasses() const;
        //virtual Properties properties() const;
    };
}

QT_END_NAMESPACE

QT_END_HEADER

#endif
