C++ Ptr::itemType方法代码示例

Expression::Ptr CastableAs::typeCheck(const StaticContext::Ptr &context,
                                      const SequenceType::Ptr &reqType)
{
    checkTargetType(context);
    const Expression::Ptr me(SingleContainer::typeCheck(context, reqType));

    return me;
    if(BuiltinTypes::xsQName->xdtTypeMatches(m_targetType->itemType()))
    {
        const SequenceType::Ptr seqt(m_operand->staticType());
        /* We can cast a string literal, an xs:QName value, and an
         * empty sequence(if empty is allowed), to xs:QName. */
        if(m_operand->is(IDStringValue) ||
           BuiltinTypes::xsQName->xdtTypeMatches(seqt->itemType()) ||
           (*seqt->itemType() == *CommonSequenceTypes::Empty && m_targetType->cardinality().allowsEmpty()))
        {
            return wrapLiteral(CommonValues::BooleanTrue, context, this)->typeCheck(context, reqType);
        }
        else
            return wrapLiteral(CommonValues::BooleanFalse, context, this)->typeCheck(context, reqType);
    }
    else
    {
        /* Let the CastingPlatform look up its AtomicCaster. */
        prepareCasting(context, m_operand->staticType()->itemType());

        return me;
    }
}

SequenceType::Ptr IfThenClause::staticType() const
{
    const SequenceType::Ptr t1(m_operand2->staticType());
    const SequenceType::Ptr t2(m_operand3->staticType());

    return makeGenericSequenceType(t1->itemType() | t2->itemType(),
                                   t1->cardinality() | t2->cardinality());
}

SequenceType::Ptr SumFN::staticType() const
{
    const SequenceType::Ptr t(m_operands.first()->staticType());

    if(m_operands.count() == 1)
    {
        return makeGenericSequenceType(t->itemType() | BuiltinTypes::xsInteger,
                                       Cardinality::exactlyOne());
    }
    else
    {
        return makeGenericSequenceType(t->itemType() | m_operands.at(1)->staticType()->itemType(),
                                       t->cardinality().toWithoutMany());
    }
}

Expression::Ptr InstanceOf::compress(const StaticContext::Ptr &context)
{
    const Expression::Ptr me(SingleContainer::compress(context));

    if(me.data() != this || m_operand->has(DisableTypingDeduction))
        return me;

    const SequenceType::Ptr opType(m_operand->staticType());
    const ItemType::Ptr itType(m_targetType->itemType());
    const ItemType::Ptr ioType(opType->itemType());

    if(m_targetType->cardinality().isMatch(opType->cardinality()))
    {
        if(itType->xdtTypeMatches(ioType))
            return wrapLiteral(CommonValues::BooleanTrue, context, this);
        else if(!ioType->xdtTypeMatches(itType))
        {
            return wrapLiteral(CommonValues::BooleanFalse, context, this);
        }
    }
    /* The cardinality is not guaranteed to match; it will need testing. */
    else if(!ioType->xdtTypeMatches(itType))
    {
        /* There's no way it's gonna match. The cardinality is not only
         * wrong, but the item type as well. */
        return wrapLiteral(CommonValues::BooleanFalse, context, this);
    }

    return me;
}

bool SequenceType::matches(const SequenceType::Ptr other) const
{
    Q_ASSERT(other);

    return itemType()->xdtTypeMatches(other->itemType()) &&
           cardinality().isMatch(other->cardinality());
}

CastableAs::CastableAs(const Expression::Ptr &operand,
                       const SequenceType::Ptr &tType) : SingleContainer(operand),
                                                         m_targetType(tType)
{
    Q_ASSERT(tType);
    Q_ASSERT(!tType->cardinality().allowsMany());
    Q_ASSERT(tType->itemType()->isAtomicType());
}

bool BySequenceTypeIdentifier::matches(const Expression::Ptr &expr) const
{
    const SequenceType::Ptr t(expr->staticType());

    return m_seqType->itemType()->xdtTypeMatches(t->itemType())
           &&
           m_seqType->cardinality().isMatch(t->cardinality());
}

SequenceType::Ptr ForClause::staticType() const
{
    const SequenceType::Ptr returnType(m_operand2->staticType());

    return makeGenericSequenceType(returnType->itemType(),
                                   m_operand1->staticType()->cardinality()
                                        * /* multiply operator */
                                   returnType->cardinality());
}

SequenceType::Ptr Path::staticType() const
{
    const SequenceType::Ptr opType(m_operand2->staticType());

    /* For each parent step, we evaluate the child step. So multiply the two
     * cardinalities. */
    return makeGenericSequenceType(opType->itemType(),
                                   m_operand1->staticType()->cardinality() * opType->cardinality());
}

Expression::Ptr CountFN::typeCheck(const StaticContext::Ptr &context,
                                   const SequenceType::Ptr &reqType)
{
    if(*CommonSequenceTypes::EBV->itemType() == *reqType->itemType())
    {
        return ByIDCreator::create(IDExistsFN, operands(), context, this)->typeCheck(context, reqType);
    }
    else
        return FunctionCall::typeCheck(context, reqType);
}

Expression::Ptr CastAs::typeCheck(const StaticContext::Ptr &context,
                                  const SequenceType::Ptr &reqType)
{
    checkTargetType(context);
    const SequenceType::Ptr seqt(m_operand->staticType());
    ItemType::Ptr t(seqt->itemType());

    /* Special case xs:QName */
    if(BuiltinTypes::xsQName->xdtTypeMatches(m_targetType->itemType()))
    {
        /* Ok, We're casting to xs:QName. */
        if(m_operand->is(IDStringValue)) /* A valid combination, let's do the cast. */
            return castToQName(context)->typeCheck(context, reqType);
        else if(BuiltinTypes::xsQName->xdtTypeMatches(t))
            return m_operand->typeCheck(context, reqType);
        else if(seqt->cardinality().isEmpty() && m_targetType->cardinality().allowsEmpty())
            return EmptySequence::create(this, context);
        else if(!(seqt->cardinality().isEmpty() && !m_targetType->cardinality().allowsEmpty()))
        {
            context->error(QtXmlPatterns::tr("When casting to %1 or types "
                                             "derived from it, the source "
                                             "value must be of the same type, "
                                             "or it must be a string literal. "
                                             "Type %2 is not allowed.")
                           .arg(formatType(context->namePool(), BuiltinTypes::xsQName))
                           .arg(formatType(context->namePool(), seqt)),
                           ReportContext::XPTY0004, this);
            return Expression::Ptr(this);
        }
    }

    const Expression::Ptr me(SingleContainer::typeCheck(context, reqType));
    /* Type may have changed, such as that atomization has been applied. */
    t = m_operand->staticType()->itemType();

    if(m_targetType->itemType()->xdtTypeMatches(t) &&
       !BuiltinTypes::xsDayTimeDuration->xdtTypeMatches(t) &&
       !BuiltinTypes::xsYearMonthDuration->xdtTypeMatches(t))
    { /* At least casting is superflorous. */
        if(m_operand->staticType()->cardinality().isMatch(m_targetType->cardinality()))
            return m_operand; /* The whole cast expression is redundant. */
        else
        { /* Only cardinality check is needed, rewrite to CardinalityVerifier. */
            return Expression::Ptr(new CardinalityVerifier(m_operand,
                                                           m_targetType->cardinality(),
                                                           ReportContext::FORG0001));
        }
    }

    /* Let the CastingPlatform look up its AtomicCaster. */
    prepareCasting(context, t);

    return me;
}

SequenceType::Ptr Aggregator::staticType() const
{
    const SequenceType::Ptr t(m_operands.first()->staticType());
    ItemType::Ptr itemType(t->itemType());

    /* Since we have types that are derived from xs:integer, this ensures that
     * the static type is xs:integer even if the argument is for
     * instance xs:unsignedShort. */
    if(BuiltinTypes::xsInteger->xdtTypeMatches(itemType) &&
       !itemType->xdtTypeMatches(BuiltinTypes::xsInteger))
    {
        itemType = BuiltinTypes::xsInteger;
    }

    return makeGenericSequenceType(itemType,
                                   t->cardinality().toWithoutMany());
}

Expression::Ptr ExpressionSequence::typeCheck(const StaticContext::Ptr &context,
                                              const SequenceType::Ptr &reqType)
{
    Q_ASSERT(reqType);
    Expression::List::iterator it(m_operands.begin());
    const Expression::List::iterator end(m_operands.end());

    /* We treat the cardinality differently here by allowing the empty sequence
     * for each individual Expression, since the Cardinality can be conformed to by
     * the ExpressionSequence as a whole(which we check for at the end). */
    const SequenceType::Ptr testOnlyIT(makeGenericSequenceType(reqType->itemType(),
                                                               Cardinality::empty() |
                                                               reqType->cardinality()));

    for(; it != end; ++it)
        *it = (*it)->typeCheck(context, testOnlyIT);

    /* The above loop is only guaranteed to find item type errors, but the cardinality
     * can still be wrong since the operands were treated individually. */
    return CardinalityVerifier::verifyCardinality(Expression::Ptr(this), reqType->cardinality(), context);
}

Expression::Ptr CastableAs::compress(const StaticContext::Ptr &context)
{
    const Expression::Ptr me(SingleContainer::compress(context));

    if(me.data() != this) /* We already managed to const fold, how convenient. */
        return me;

    const AtomicType::Ptr t(m_targetType->itemType());

    const SequenceType::Ptr opType(m_operand->staticType());

    /* Casting to these always succeeds. */
    if(*t == *BuiltinTypes::xsString ||
       *t == *BuiltinTypes::xsUntypedAtomic ||
       (*t == *opType->itemType() &&
       (m_targetType->cardinality().isMatch(opType->cardinality()))))
    {
        return wrapLiteral(CommonValues::BooleanTrue, context, this);
    }
    else
        return me;
}

Expression::Ptr InstanceOf::compress(const StaticContext::Ptr &context)
{
    const Expression::Ptr me(SingleContainer::compress(context));

    if(me != this || m_operand->has(DisableTypingDeduction))
        return me;

    const SequenceType::Ptr opType(m_operand->staticType());
    const ItemType::Ptr targetType(m_targetType->itemType());
    const ItemType::Ptr operandType(opType->itemType());

    if(m_targetType->cardinality().isMatch(opType->cardinality()))
    {
        if(*operandType == *CommonSequenceTypes::Empty || targetType->xdtTypeMatches(operandType))
            return wrapLiteral(CommonValues::BooleanTrue, context, this);
        else if(!operandType->xdtTypeMatches(targetType))
            return wrapLiteral(CommonValues::BooleanFalse, context, this);
    }
    /* Optimization: rule out the case where instance of will always fail. */

    return me;
}