summaryrefslogtreecommitdiffstats
path: root/src/xmlpatterns/expr/qexpressionfactory_p.h
blob: 2d1692747abb94265e20d4a4ae4d78e9a00e46b1 (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
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
/****************************************************************************
**
** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/
**
** 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.
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists purely as an
// implementation detail.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.

#ifndef Patternist_ExpressionFactory_H
#define Patternist_ExpressionFactory_H

#include <QXmlQuery>

#include "qexpression_p.h"
#include "qtokenizer_p.h"

#include <QSharedData>
#include <QUrl>

QT_BEGIN_HEADER

QT_BEGIN_NAMESPACE

class QIODevice;

namespace QPatternist
{
    /**
     * @short The central entry point for compiling expressions.
     *
     * @ingroup Patternist_expressions
     * @author Frans Englich <frans.englich@nokia.com>
     */
    class Q_AUTOTEST_EXPORT ExpressionFactory : public QSharedData
    {
    public:
        typedef QExplicitlySharedDataPointer<ExpressionFactory> Ptr;

        /**
         * @short This constructor cannot be synthesized since we
         * use the Q_DISABLE_COPY macro.
         */
        inline ExpressionFactory()
        {
        }

        virtual ~ExpressionFactory()
        {
        }

        enum CompilationStage
        {
            QueryBodyInitial        = 1,
            QueryBodyTypeCheck      = 1 << 1,
            QueryBodyCompression    = 1 << 2,
            UserFunctionTypeCheck   = 1 << 3,
            UserFunctionCompression = 1 << 4,
            GlobalVariableTypeCheck = 1 << 5
        };

        /**
         * Creates a compiled representation of the XPath expression @p expr, with Static
         * Context information supplied via @p context. This is for example whether the expression
         * is an XPath 1.0 or XPath 2.0 expression, or what functions that are available.
         *
         * @p requiredType specifies what type results of the evaluating the expression
         * must match. Passing CommonValues::ZeroOrMoreItems allows anything as result, while
         * passing CommonSequenceTypes::EBV means anything but an Effective %Boolean Value extractable
         * result is a type error, for example.
         *
         * @note An empty @p expr is an invalid XPath expression. It will be reported as such,
         * but it is neverthless the caller's resonsibility to ensure that it's not that(since
         * it is likely invalid already in the medium it was stored).
         */
        virtual Expression::Ptr createExpression(const QString &expr,
                                                 const StaticContext::Ptr &context,
                                                 const QXmlQuery::QueryLanguage lang,
                                                 const SequenceType::Ptr &requiredType,
                                                 const QUrl &queryURI,
                                                 const QXmlName &initialTemplateName);

        virtual Expression::Ptr createExpression(QIODevice *const device,
                                                 const StaticContext::Ptr &context,
                                                 const QXmlQuery::QueryLanguage lang,
                                                 const SequenceType::Ptr &requiredType,
                                                 const QUrl &queryURI,
                                                 const QXmlName &initialTemplateName);

        /**
         * Finds the last paths of a set of paths(if any) and tells the Path
         * so, such that it can generate the code for checking XPTY0018.
         *
         * Must be called before typeCheck() is called on the operand, since
         * the typeCheck() uses the information for type checking.
         */
        static void registerLastPath(const Expression::Ptr &operand);

    protected:
        enum TemplateCompilationStage
        {
            TemplateInitial         = 1,
            TemplateTypeCheck       = 1 << 1,
            TemplateCompress        = 1 << 2
        };

        /**
         * This function is called by createExpression() each time
         * after a pass on the AST has been completed. Under a typical
         * compilation this function is thus called three times: after the initial
         * build, after the Expression::typeCheck() stage, and after
         * Expression::compress(). @p tree is the AST after each pass.
         *
         * This mechanism is currently used for debugging, since it provides a
         * way of introspecting what the compilation process do to the tree. The
         * current implementation do nothing.
         */
        virtual void processTreePass(const Expression::Ptr &tree,
                                     const CompilationStage stage);

        virtual void processTemplateRule(const Expression::Ptr &body,
                                         const TemplatePattern::Ptr &pattern,
                                         const QXmlName &mode,
                                         const TemplateCompilationStage stage);

        virtual void processNamedTemplate(const QXmlName &name,
                                          const Expression::Ptr &tree,
                                          const TemplateCompilationStage stage);

        Expression::Ptr createExpression(const Tokenizer::Ptr &tokenizer,
                                         const StaticContext::Ptr &context,
                                         const QXmlQuery::QueryLanguage lang,
                                         const SequenceType::Ptr &requiredType,
                                         const QUrl &queryURI,
                                         const QXmlName &initialTemplateName);
    private:
        Q_DISABLE_COPY(ExpressionFactory)
    };
}

QT_END_NAMESPACE

QT_END_HEADER

#endif