source: trunk/src/xmlpatterns/expr/qexpression.cpp@ 197

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#include "qboolean_p.h"
#include "qcommonvalues_p.h"
#include "qemptysequence_p.h"
#include "qliteral_p.h"
#include "qliteralsequence_p.h"
#include "qoperandsiterator_p.h"
#include "qoptimizerframework_p.h"
#include "qstaticfocuscontext_p.h"
#include "qtypechecker_p.h"

#include "qexpression_p.h"

QT_BEGIN_NAMESPACE

using namespace QPatternist;

Expression::~Expression()
{
}

StaticContext::Ptr Expression::finalizeStaticContext(const StaticContext::Ptr &context) const
{
    Q_ASSERT(context);
    const ItemType::Ptr focusType(newFocusType());
    Q_ASSERT(focusType);
    return StaticContext::Ptr(new StaticFocusContext(focusType, context));
}

Expression::Ptr Expression::typeCheck(const StaticContext::Ptr &context,
                                      const SequenceType::Ptr &reqType)
{
    Q_ASSERT(reqType);
    typeCheckOperands(context);
    return TypeChecker::applyFunctionConversion(Expression::Ptr(this), reqType, context);
}

void Expression::typeCheckOperands(const StaticContext::Ptr &context)
{
    const Expression::List ops(operands());

    /* Check if this expression has any operands at all. */
    if(ops.isEmpty())
        return; /* We're done, early exit. */

    const SequenceType::List opTypes(expectedOperandTypes());
    Expression::List result;

    /* If we create a focus, we handle the last one specially, so avoid it in the loop. */
    const bool createsFocus = has(CreatesFocusForLast);
    const SequenceType::List::const_iterator typeEnd(createsFocus ? --opTypes.constEnd()
                                                                  : opTypes.constEnd());
    const Expression::List::const_iterator end(createsFocus ? --ops.constEnd()
                                                            : ops.constEnd());

    SequenceType::List::const_iterator reqType(opTypes.constBegin());
    SequenceType::Ptr t(*reqType);
    // TODO we assign twice to t here(also below in loop) when ops.size() > 1

    Expression::List::const_iterator it(ops.constBegin());