summaryrefslogtreecommitdiffstats
path: root/src/xmlpatterns/expr/qcastableas.cpp
blob: e9c4fbefa5d6a7c6a7e11506e10f4f5c583157c8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
/****************************************************************************
**
** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtXmlPatterns module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** GNU Lesser General Public License Usage
** This file may be used under the terms of the GNU Lesser General Public
** License version 2.1 as published by the Free Software Foundation and
** appearing in the file LICENSE.LGPL included in the packaging of this
** file. Please review the following information to ensure the GNU Lesser
** General Public License version 2.1 requirements will be met:
** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU General
** Public License version 3.0 as published by the Free Software Foundation
** and appearing in the file LICENSE.GPL included in the packaging of this
** file. Please review the following information to ensure the GNU General
** Public License version 3.0 requirements will be met:
** http://www.gnu.org/copyleft/gpl.html.
**
** Other Usage
** Alternatively, this file may be used in accordance with the terms and
** conditions contained in a signed written agreement between you and Nokia.
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include "qatomictype_p.h"
#include "qitem_p.h"
#include "qboolean_p.h"
#include "qbuiltintypes_p.h"
#include "qcommonsequencetypes_p.h"
#include "qcommonvalues_p.h"
#include "qliteral_p.h"

#include "qcastableas_p.h"

QT_BEGIN_NAMESPACE

using namespace QPatternist;

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 CastableAs::evaluateEBV(const DynamicContext::Ptr &context) const
{
    Item item;

    if(m_operand->staticType()->cardinality().allowsMany())
    {
        const Item::Iterator::Ptr it(m_operand->evaluateSequence(context));
        item = it->next();

        if(it->next())
            return false;
    }
    else
        item = m_operand->evaluateSingleton(context);

    if(item)
        return !cast(item, context).as<AtomicValue>()->hasError();
    else
        return m_targetType->cardinality().allowsEmpty();
}

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

    if(me != 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, assuming the cardinality also matches,
     * although the cardinality can fail. */
    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 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::List CastableAs::expectedOperandTypes() const
{
    SequenceType::List result;
    result.append(CommonSequenceTypes::ZeroOrMoreAtomicTypes);
    return result;
}

SequenceType::Ptr CastableAs::staticType() const
{
    return CommonSequenceTypes::ExactlyOneBoolean;
}

ExpressionVisitorResult::Ptr CastableAs::accept(const ExpressionVisitor::Ptr &visitor) const
{
    return visitor->visit(this);
}

QT_END_NAMESPACE