1 /****************************************************************************
3 ** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
4 ** All rights reserved.
5 ** Contact: Nokia Corporation (qt-info@nokia.com)
7 ** This file is part of the QtXmlPatterns module of the Qt Toolkit.
9 ** $QT_BEGIN_LICENSE:LGPL$
10 ** No Commercial Usage
11 ** This file contains pre-release code and may not be distributed.
12 ** You may use this file in accordance with the terms and conditions
13 ** contained in the Technology Preview License Agreement accompanying
16 ** GNU Lesser General Public License Usage
17 ** Alternatively, this file may be used under the terms of the GNU Lesser
18 ** General Public License version 2.1 as published by the Free Software
19 ** Foundation and appearing in the file LICENSE.LGPL included in the
20 ** packaging of this file. Please review the following information to
21 ** ensure the GNU Lesser General Public License version 2.1 requirements
22 ** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
24 ** In addition, as a special exception, Nokia gives you certain additional
25 ** rights. These rights are described in the Nokia Qt LGPL Exception
26 ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
28 ** If you have questions regarding the use of this file, please contact
29 ** Nokia at qt-info@nokia.com.
40 ****************************************************************************/
42 #include "qatomictype_p.h"
44 #include "qboolean_p.h"
45 #include "qbuiltintypes_p.h"
46 #include "qcommonsequencetypes_p.h"
47 #include "qcommonvalues_p.h"
48 #include "qliteral_p.h"
50 #include "qcastableas_p.h"
54 using namespace QPatternist;
56 CastableAs::CastableAs(const Expression::Ptr &operand,
57 const SequenceType::Ptr &tType) : SingleContainer(operand),
61 Q_ASSERT(!tType->cardinality().allowsMany());
62 Q_ASSERT(tType->itemType()->isAtomicType());
65 bool CastableAs::evaluateEBV(const DynamicContext::Ptr &context) const
69 if(m_operand->staticType()->cardinality().allowsMany())
71 const Item::Iterator::Ptr it(m_operand->evaluateSequence(context));
78 item = m_operand->evaluateSingleton(context);
81 return !cast(item, context).as<AtomicValue>()->hasError();
83 return m_targetType->cardinality().allowsEmpty();
86 Expression::Ptr CastableAs::compress(const StaticContext::Ptr &context)
88 const Expression::Ptr me(SingleContainer::compress(context));
90 if(me != this) /* We already managed to const fold, how convenient. */
93 const AtomicType::Ptr t(m_targetType->itemType());
95 const SequenceType::Ptr opType(m_operand->staticType());
97 /* Casting to these always succeeds, assuming the cardinality also matches,
98 * although the cardinality can fail. */
99 if(( *t == *BuiltinTypes::xsString
100 || *t == *BuiltinTypes::xsUntypedAtomic
101 || *t == *opType->itemType())
102 &&(m_targetType->cardinality().isMatch(opType->cardinality())))
104 return wrapLiteral(CommonValues::BooleanTrue, context, this);
110 Expression::Ptr CastableAs::typeCheck(const StaticContext::Ptr &context,
111 const SequenceType::Ptr &reqType)
113 checkTargetType(context);
114 const Expression::Ptr me(SingleContainer::typeCheck(context, reqType));
117 if(BuiltinTypes::xsQName->xdtTypeMatches(m_targetType->itemType()))
119 const SequenceType::Ptr seqt(m_operand->staticType());
120 /* We can cast a string literal, an xs:QName value, and an
121 * empty sequence(if empty is allowed), to xs:QName. */
122 if(m_operand->is(IDStringValue) ||
123 BuiltinTypes::xsQName->xdtTypeMatches(seqt->itemType()) ||
124 (*seqt->itemType() == *CommonSequenceTypes::Empty && m_targetType->cardinality().allowsEmpty()))
126 return wrapLiteral(CommonValues::BooleanTrue, context, this)->typeCheck(context, reqType);
129 return wrapLiteral(CommonValues::BooleanFalse, context, this)->typeCheck(context, reqType);
133 /* Let the CastingPlatform look up its AtomicCaster. */
134 prepareCasting(context, m_operand->staticType()->itemType());
140 SequenceType::List CastableAs::expectedOperandTypes() const
142 SequenceType::List result;
143 result.append(CommonSequenceTypes::ZeroOrMoreAtomicTypes);
147 SequenceType::Ptr CastableAs::staticType() const
149 return CommonSequenceTypes::ExactlyOneBoolean;
152 ExpressionVisitorResult::Ptr CastableAs::accept(const ExpressionVisitor::Ptr &visitor) const
154 return visitor->visit(this);