qsequencefns_p.h

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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_SequenceFNs_H
#define Patternist_SequenceFNs_H

#include "qatomiccomparator_p.h"
#include "qcomparisonplatform_p.h"
#include "qliteral_p.h"
#include "qfunctioncall_p.h"

QT_BEGIN_HEADER

QT_BEGIN_NAMESPACE

namespace QPatternist
{
    class BooleanFN : public FunctionCall
    {
    public:
        virtual bool evaluateEBV(const DynamicContext::Ptr &context) const;

        virtual Expression::Ptr typeCheck(const StaticContext::Ptr &context,
                                          const SequenceType::Ptr &reqType);
    };

    class IndexOfFN : public FunctionCall,
                      public ComparisonPlatform<IndexOfFN, false>
    {
    public:
        inline IndexOfFN() : ComparisonPlatform<IndexOfFN, false>()
        {
        }

        virtual Item::Iterator::Ptr evaluateSequence(const DynamicContext::Ptr &context) const;
        virtual Expression::Ptr typeCheck(const StaticContext::Ptr &context,
                                          const SequenceType::Ptr &reqType);

        inline AtomicComparator::Operator operatorID() const
        {
            return AtomicComparator::OperatorEqual;
        }
    };

    template<const Expression::ID Id>
    class Existence : public FunctionCall
    {
    public:
        virtual bool evaluateEBV(const DynamicContext::Ptr &context) const
        {
            if(Id == IDExistsFN)
                return !m_operands.first()->evaluateSequence(context)->isEmpty();
            else
                return m_operands.first()->evaluateSequence(context)->isEmpty();
        }

        virtual Expression::Ptr compress(const StaticContext::Ptr &context)
        {
            // RVCT doesn't like using template parameter in trinary operator when the trinary operator result is
            // passed directly into another constructor. 
            Q_ASSERT(Id == IDExistsFN || Id == IDEmptyFN);

            const Expression::Ptr me(FunctionCall::compress(context));

            if(me != this)
                return me;

            // RVCT doesn't like using template parameter in trinary operator when the trinary operator result is
            // passed directly into another constructor. 
            Expression::ID tempId = Id;
            const Cardinality myCard((tempId == IDExistsFN) ? Cardinality::oneOrMore() : Cardinality::empty());

            const Cardinality card(m_operands.first()->staticType()->cardinality());
            if(myCard.isMatch(card))
            { /* Since the dynamic type always is narrower than the static type or equal, and that the
                 static type is in scope, it means we will always be true. */
                return wrapLiteral(CommonValues::BooleanTrue, context, this);
            }
            else
            {
                /* Is it even possible to hit? */
                if(myCard.canMatch(card))
                {
                    return me;
                }
                else
                { /* We can never hit. */
                    return wrapLiteral(CommonValues::BooleanFalse, context, this);
                }
            }
        }
    };

    class DistinctValuesFN : public FunctionCall,
                             public ComparisonPlatform<IndexOfFN, false>
    {
    public:
        inline DistinctValuesFN() : ComparisonPlatform<IndexOfFN, false>()
        {
        }

        virtual Item::Iterator::Ptr evaluateSequence(const DynamicContext::Ptr &context) const;
        virtual Expression::Ptr typeCheck(const StaticContext::Ptr &context,
                                          const SequenceType::Ptr &reqType);
        virtual SequenceType::Ptr staticType() const;

    protected:
        inline AtomicComparator::Operator operatorID() const
        {
            return AtomicComparator::OperatorEqual;
        }
    };

    class InsertBeforeFN : public FunctionCall
    {
    public:
        virtual Item::Iterator::Ptr evaluateSequence(const DynamicContext::Ptr &context) const;
        virtual Item evaluateSingleton(const DynamicContext::Ptr &context) const;

        virtual SequenceType::Ptr staticType() const;
    };

    class RemoveFN : public FunctionCall
    {
    public:
        virtual Item::Iterator::Ptr evaluateSequence(const DynamicContext::Ptr &context) const;
        virtual Item evaluateSingleton(const DynamicContext::Ptr &context) const;

        virtual SequenceType::Ptr staticType() const;
    };

    class ReverseFN : public FunctionCall
    {
    public:

        virtual Item::Iterator::Ptr evaluateSequence(const DynamicContext::Ptr &context) const;
        virtual Expression::Ptr typeCheck(const StaticContext::Ptr &context,
                                          const SequenceType::Ptr &reqType);

        virtual SequenceType::Ptr staticType() const;
    };

    class SubsequenceFN : public FunctionCall
    {
    public:
        SubsequenceFN();
        virtual Item::Iterator::Ptr evaluateSequence(const DynamicContext::Ptr &context) const;
        virtual Item evaluateSingleton(const DynamicContext::Ptr &context) const;

        virtual Expression::Ptr typeCheck(const StaticContext::Ptr &context,
                                          const SequenceType::Ptr &reqType);

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

        virtual SequenceType::Ptr staticType() const;

    private:
        bool m_hasTypeChecked;
    };
}

QT_END_NAMESPACE

QT_END_HEADER

#endif