QPatternist::BooleanComparator Class Reference

Compares xs:boolean values. More...

#include <qatomiccomparators_p.h>

Inheritance diagram for QPatternist::BooleanComparator:

Public Functions
virtual ComparisonResult	compare (const Item &op1, const AtomicComparator::Operator op, const Item &op2) const
virtual bool	equals (const Item &op1, const Item &op2) const
Public Functions inherited from QPatternist::AtomicComparator
	AtomicComparator ()
virtual	~AtomicComparator ()
Public Functions inherited from QPatternist::AtomicTypeVisitorResult
	AtomicTypeVisitorResult ()
virtual	~AtomicTypeVisitorResult ()
Public Functions inherited from QSharedData
	QSharedData ()
	Constructs a QSharedData object with a reference count of 0. More...
	QSharedData (const QSharedData &)
	Constructs a QSharedData object with reference count 0. More...

Additional Inherited Members
Public Types inherited from QPatternist::AtomicComparator
enum	ComparisonResult { LessThan = 1, Equal = 2, GreaterThan = 4, Incomparable = 8 }
enum	ComparisonType { AsGeneralComparison = 1, AsValueComparison }
enum	Operator {   OperatorEqual = 1, OperatorNotEqual = 1 << 1, OperatorGreaterThan = 1 << 2, OperatorLessThan = 1 << 3,   OperatorLessThanNaNLeast = 1 << 4, OperatorLessThanNaNGreatest = 1 << 5, OperatorGreaterOrEqual = OperatorEqual | OperatorGreaterThan, OperatorLessOrEqual = OperatorEqual | OperatorLessThan }
typedef QFlags< Operator >	Operators
typedef QExplicitlySharedDataPointer< AtomicComparator >	Ptr
Public Types inherited from QPatternist::AtomicTypeVisitorResult
typedef QExplicitlySharedDataPointer< AtomicTypeVisitorResult >	Ptr
Static Public Functions inherited from QPatternist::AtomicComparator
static QString	displayName (const AtomicComparator::Operator op, const ComparisonType type)
Public Variables inherited from QSharedData
QAtomicInt	ref

Detailed Description

Compares xs:boolean values.

This is done via the object's Boolean::evaluteEBV() function.

Author

Frans Englich frans.nosp@m..eng.nosp@m.lich@.nosp@m.noki.nosp@m.a.com

Definition at line 148 of file qatomiccomparators_p.h.

Functions

compare()

AtomicComparator::ComparisonResult BooleanComparator::compare ( const Item &  op1, const AtomicComparator::Operator  op, const Item &  op2  ) const

virtual

Compares op1 and op2 and determines the relationship between the two. This is used for sorting and comparisons. The implementation performs an assert crash, and must therefore be re-implemented if comparing the relevant values should be possible.

Parameters

op1	the first operand
op	the operator. How a comparison is carried out shouldn't depend on what the operator is, but in some cases it is of interest.
op2	the second operand

Reimplemented from QPatternist::AtomicComparator.

Definition at line 124 of file qatomiccomparators.cpp.

{
    /* We know Boolean::evaluateEBV doesn't use the DynamicContext. */
    const bool v1 = o1.as<AtomicValue>()->evaluateEBV(QExplicitlySharedDataPointer<DynamicContext>());
    const bool v2 = o2.as<AtomicValue>()->evaluateEBV(QExplicitlySharedDataPointer<DynamicContext>());

    if(v1 == v2)
        return Equal;
    else if(v1 == false)
    {
        Q_ASSERT(v2 == true);
        return LessThan;
    }
    else
    {
        Q_ASSERT(v1 == true && v2 == false);
        return GreaterThan;
    }
}

equals()

bool BooleanComparator::equals ( const Item &  op1, const Item &  op2  ) const

virtual

Determines whether op1 and op2 are equal. It is the same as calling compare() and checking whether the return value is Equal, but since comparison testing is such a common operation, this specialized function exists.

Returns

true if op1 and op2 are equal.

Parameters

op1	the first operand
op2	the second operand

Implements QPatternist::AtomicComparator.

Definition at line 146 of file qatomiccomparators.cpp.

{
    /* Boolean is an atomic class. */
    return o1.as<AtomicValue>() == o2.as<AtomicValue>();
}

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The documentation for this class was generated from the following files:

• /src/xmlpatterns/data/qatomiccomparators_p.h
• /src/xmlpatterns/data/qatomiccomparators.cpp