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
|
/****************************************************************************
**
** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the QtXmlPatterns module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Digia. For licensing terms and
** conditions see http://qt.digia.com/licensing. For further information
** use the contact form at http://qt.digia.com/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, 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, Digia gives you certain additional
** rights. These rights are described in the Digia 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.
**
**
** $QT_END_LICENSE$
**
****************************************************************************/
//
// 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.
/**
* @file
* @short Contains Doxygen documentation for groups.
*/
namespace QPatternist
{
/**
* @short The abstract syntax tree nodes that implements the builtin
* functions, such as @c fn:concat().
*
* @defgroup Patternist_functions Function Implementations
* @author Frans Englich <frans.englich@nokia.com>
*/
/**
* @short The abstract syntax tree nodes that is generated for XPath,
* XQuery, and XSL-T code.
*
* XPath's approach of compilation is traditional. An Abstract Syntax
* Tree(AST) is built, where the Expression class is the abstract base
* class for all kinds of implementations of expressions.
*
* What perhaps can be said to be characteristic for Patternist is that the
* base class, Expression, performs a lot of work, and that sub-classes
* declares what specific behaviors they need, which the Expression's
* functions then bring into action.
*
* XPath expressions often have different amount of operands. For example,
* the 'and' expression takes two, the context item(".") none, and the
* if-expression three. To help expression implementations with that, there
* exist the abstract EmptyContainer, SingleContainer, PairContainer,
* TripleContainer, and UnlimitedContainer classes for avoiding duplicating
* code.
*
* @defgroup Patternist_expressions Expressions
* @author Frans Englich <frans.englich@nokia.com>
*/
/**
* @short Various classes that contains small utility functions.
*
* @defgroup Patternist Utility Classes
* @author Frans Englich <frans.englich@nokia.com>
*/
/**
* @short Classes for the type system in the XQuery & XSL-T language.
*
* @defgroup Patternist_types Type system
* @author Frans Englich <frans.englich@nokia.com>
*/
/**
* @defgroup Patternist_xdm XQuery/XPath Data Model
* @author Frans Englich <frans.englich@nokia.com>
*/
/**
* @short Patternist's family of iterators in one of the most central parts
* of Patternist's API, and are responsible for carrying, and typically
* also creating, data.
*
* An iterator, which always is an Iterator sub-class, is similar to a
* Java-style iterator. What signifies Patternist's iterators is that they
* almost always contains business logic(which is the cause to their
* efficiency).
*
* An example which illustrates this principle is the RangeIterator. When
* the RangeExpression is told to create a sequence of integers between 1
* and 1000, it doesn't enter a loop that allocates 1000 Integer instances,
* but instead return an RangeIterator that incrementally creates the
* numbers when asked to do so via its RangeIterator::next() function. If
* it turns out that the expression that has the range expression as
* operand only needs three items from it, that is what gets created, not
* 1000.
*
* All iterators operates by that principle, perhaps suitably labeled as
* "pull-based", "lazy loaded" or "serialized". Central for the XPath
* language is that it filters and selects data, and the iterators supports
* this well by letting the demand of the filter expressions(the callees)
* decide how "much" source that gets computed. In this way the evaluation
* of an expression tree can lead to a chain of pipelined iterators, where
* the first asks the second for data and then performs its specific
* operations, the second subsequently asks the third, and so forth.
*
* However, the iterators are not limited to be used for representing
* sequences of items in the XPath Data Model. The Iterator is
* parameterized on one argument, meaning any type of "units" can be
* iterated, be it Item or any other. One use of this is in the
* ExpressionSequence(which implements the comma operator) where it creates
* Iterator instances over Expression instances -- its operands. The
* parameterization is often used in combination with the MappingIterator
* and the MappingCallback.
*
* @defgroup Patternist_iterators Iterators
* @author Frans Englich <frans.englich@nokia.com>
*/
}
|
