QPatternist::TraceCallback Class Reference

TraceCallback is a MappingCallback and takes care of the tracing of each individual item. More...

Inheritance diagram for QPatternist::TraceCallback:

Public Types
typedef QExplicitlySharedDataPointer< TraceCallback >	Ptr

Public Functions
Item	mapToItem (const Item &item, const DynamicContext::Ptr &context)
	TraceCallback (const QString &msg)
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...

Properties
const QString	m_msg
xsInteger	m_position

Additional Inherited Members
Public Variables inherited from QSharedData
QAtomicInt	ref

Detailed Description

TraceCallback is a MappingCallback and takes care of the tracing of each individual item.

Because Patternist must be thread safe, TraceFN creates a TraceCallback each time the function is evaluated. In other words, TraceFN, which is an Expression sub class, can't modify its members, but MappingCallback does not have this limitation since it's created on a per evaluation basis.

Author

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

Definition at line 66 of file qtracefn.cpp.

Typedefs

Ptr

typedef QExplicitlySharedDataPointer<TraceCallback> QPatternist::TraceCallback::Ptr

Definition at line 69 of file qtracefn.cpp.

Constructors and Destructors

TraceCallback()

QPatternist::TraceCallback::TraceCallback ( const QString &  msg )

inline

Definition at line 71 of file qtracefn.cpp.

Referenced by QPatternist::TraceFN::evaluateSequence(), and QPatternist::TraceFN::evaluateSingleton().

                                                 : m_position(0),
                                                   m_msg(msg)
        {
        }

Functions

mapToItem()

Item QPatternist::TraceCallback::mapToItem ( const Item &  item, const DynamicContext::Ptr &  context  )

inline

Performs the actual tracing.

Definition at line 79 of file qtracefn.cpp.

        {
            QTextStream out(stderr);
            ++m_position;
            if(m_position == 1)
            {
                if(item)
                {
                    out << qPrintable(m_msg)
                        << " : "
                        << qPrintable(item.stringValue());
                }
                else
                {
                    out << qPrintable(m_msg)
                        << " : ("
                        << qPrintable(formatType(context->namePool(), CommonSequenceTypes::Empty))
                        << ")\n";
                    return Item();
                }
            }
            else
            {
                out << qPrintable(item.stringValue())
                    << '['
                    << m_position
                    << "]\n";
            }

            return item;
        }

Properties

m_msg

const QString QPatternist::TraceCallback::m_msg

private

Definition at line 114 of file qtracefn.cpp.

Referenced by mapToItem().

m_position

xsInteger QPatternist::TraceCallback::m_position

private

Definition at line 113 of file qtracefn.cpp.

Referenced by mapToItem().

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

• /src/xmlpatterns/functions/qtracefn.cpp