-
Paul Wicking authored
Change-Id: Id62ceaac5a34b165026ee81fa504dedaa0ecb1bd Reviewed-by:Martin Smith <martin.smith@qt.io>
b1299590
/******************************************************************************** Copyright (C) 2016 The Qt Company Ltd.** Contact: https://www.qt.io/licensing/**** This file is part of the documentation of the Qt Toolkit.**** $QT_BEGIN_LICENSE:FDL$** 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 The Qt Company. For licensing terms** and conditions see https://www.qt.io/terms-conditions. For further** information use the contact form at https://www.qt.io/contact-us.**** GNU Free Documentation License Usage** Alternatively, this file may be used under the terms of the GNU Free** Documentation License version 1.3 as published by the Free Software** Foundation and appearing in the file included in the packaging of** this file. Please review the following information to ensure** the GNU Free Documentation License version 1.3 requirements** will be met: https://www.gnu.org/licenses/fdl-1.3.html.** $QT_END_LICENSE$******************************************************************************//*! \page 14-qdoc-commands-contextcommands.html \previouspage Topic Commands \contentspage QDoc Manual \nextpage Document Navigation \title Context Commands The context commands provide information about the element being documented that QDoc can't deduce on its own. For example: \list \li Is this class thread-safe? \li Is this function reentrant? \li Of which module is this class a member ? \endlist Context commands can appear anywhere in a QDoc comment, but they are normally placed near the top of the comment, just below the \l {Topic Commands} {topic} command. \list \li \l {abstract-command} {\\abstract} \li \l {contentspage-command}{\\contentspage}, \li \l {ingroup-command}{\\ingroup}, \li \l {inherits-command}{\\inherits}, \li \l {inmodule-command}{\\inmodule}, \li \l {internal-command}{\\internal}, \li \l {nextpage-command}{\\nextpage}, \li \l {nonreentrant-command}{\\nonreentrant}, \li \l {obsolete-command}{\\obsolete}, \li \l {overload-command}{\\overload}, \li \l {preliminary-command}{\\preliminary}, \li \l {previouspage-command}{\\previouspage}, \li \l {qmlabstract-command} {\\qmlabstract} \li \l {reentrant-command}{\\reentrant}, \li \l {reimp-command}{\\reimp}, \li \l {relates-command}{\\relates}, \li \l {since-command}{\\since}, \li \l {startpage-command}{\\startpage}, \li \l {subtitle-command}{\\subtitle} \li \l {threadsafe-command}{\\threadsafe}, \li \l {title-command}{\\title} \endlist7172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140
*/
/*!
\page 15-qdoc-commands-navigation.html
\previouspage Context Commands
\contentspage QDoc Manual
\nextpage Status
\title Document Navigation
The navigation commands are for linking the pages of a document in
a meaningful sequence. Below is a sequence of QDoc comments that
shows a typical use of the navigation commands.
\section1 Example
\quotefile files/basicqt.qdoc.sample
QDoc renders the "Getting Started" page in \c{creatingdialogs.html}:
\quotation
\raw HTML
<table border="0" cellpadding="0" cellspacing="5" width="100%">
<tr>
<p>
[Previous: <a href="15-qdoc-commands-navigation.html#deadlink">
Basic Qt</a>]
[<a href="15-qdoc-commands-navigation.html#deadlink">Contents</a>]
[Next: <a href="15-qdoc-commands-navigation.html#deadlink">
Creating Dialogs</a>]
</p>
<h1 align="center">Getting Started<br /></h1>
<p>
This chapter shows how to combine basic C++ with the
functionality provided by Qt to create a few small graphical
interface (GUI) applications.
</p>
<p>
[Previous: <a href="15-qdoc-commands-navigation.html#deadlink">
Basic Qt</a>]
[<a href="15-qdoc-commands-navigation.html#deadlink">Contents</a>]
[Next: <a href="15-qdoc-commands-navigation.html#deadlink">
Creating Dialogs</a>]
</p>
</table>
\endraw
\endquotation
The \l {startpage-command} {\\startpage} command creates a link to
the page the author wants as the first page of a multipage document.
The link is included in the generated HTML source code but has no
visual effect on the documentation:
\code
<head>
...
<link rel="start" href="basicqt.html" />
...
</head>
\endcode
\section1 Commands
\target previouspage-command
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\section2 \\previouspage
The \\previouspage command links the current page to the previous
page in a sequence.a The command has two arguments, each enclosed
by curly braces: the first is the link target (the title of
the previous page), the second is the link text. If the page's
title is equivalent to the link text, the second argument can be
omitted.
The command must stand alone on its own line.
\target nextpage-command
\section2 \\nextpage
The \\nextpage command links the current page to the next page in
a sequence. The command follows the same syntax and argument
convention as the \l {previouspage-command} {\\previouspage}
command.
\target startpage-command
\section2 \\startpage
The \\startpage command specifies the first page of a sequence of
pages. The command must stand alone on its own line, and its
unique argument is the title of the first document.
QDoc will generate a link to the start page and include it in the
generated HTML file, but this has no visual effect on the
documentation. The generated link type tells browsers and search
engines which document is considered by the author to be the
starting point of the collection.
\target contentspage-command
\section2 \\contentspage
The \\contentspage command links the current page to a table of
contents page. The command follows the same syntax and argument
convention as the \l {previouspage-command} {\\previouspage}
command.
*/
/*!
\page 16-qdoc-commands-status.html
\previouspage Document Navigation
\contentspage QDoc Manual
\nextpage Thread Support
\title Status
These commands are for indicating that a documented element has
some special status. The element could be marked as about to be
made obsolete, or that it is simply not to be included in the public
interface. The \l {since-command}{\\since} command is for
specifying the version number in which a function or class first
appeared. The \l {qmlabstract-command} {\\qmlabstract} command is
for marking a QML type as an abstract base class.
\target abstract-command
\target qmlabstract-command
\section1 \\abstract and \\qmlabstract
\\abstract is a synonym for the \\qmlabstract command. Add this
command to the \l {qmltype-command} {\\qmltype} comment for a QML
type when that type is meant to be used \e {only} as an abstract
base type. When a QML type is abstract, it means that the QML type
that can't be instantiated. Instead, the properties in its public
API are included in the public properties list on the reference
page for each QML type that inherits the abstract QML type. The
properties are documented as if they are properties of the
inheriting QML type.
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Normally, when a QML type is marked with \e{\\qmlabstract}, it is
also marked with \e{\\internal} so that its reference page is not
generated. It the abstract QML type is not marked internal, it
will have a reference page in the documentation.
\target default-command
\section1 \\default
The \\default command is for marking a QML property as the
\l {default-properties}
{default property}. The word \c default is displayed in
the documentation of the property.
\code
/ *!
\qmlproperty list<Change> State::changes
This property holds the changes to apply for this state.
\default
By default these changes are applied against the default state. If the state
extends another state, then the changes are applied against the state being
extended.
* /
\endcode
See how QDoc renders this property on the reference page for the
\l {State::changes}{State} type.
\target dontdocument-command
\section1 \\dontdocument
The \\dontdocument command is only used in a dontdocument.qdoc file
for a particular module. This file specifies publically declared
classes or structs that are not meant to be documented. QDoc will
not print warnings about missing \\class comments for these classes
and structs.
Below you will find the \\dontdocument command in the
dontdocument.qdoc for widgets:
\badcode
/ *!
\dontdocument (QTypeInfo QMetaTypeId)
* /
\endcode
\target obsolete-command
\section1 \\obsolete
The \\obsolete command is for indicating that a function is being
deprecated, and it should no longer be used in new code. There is
no guarantee for how long it will remain in the library.
The command must stand on its own line.
When generating the reference documentation for a class, QDoc will
create and link to a separate page documenting its obsolete
functions. Usually an equivalent function is provided as an
alternative.
\code
/ *!
\fn MyClass::MyObsoleteFunction
\obsolete
Use MyNewFunction() instead.
* /
\endcode
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QDoc renders this in \c{myclass-obsolete.html} as:
\quotation
\raw HTML
<h1>Obsolete Members for MyClass</h1>
\endraw
\b {The following class members are obsolete.} They are
provided to keep old source code working. We strongly advise
against using them in new code.
...
\list
\li void MyObsoleteFunction() \c (obsolete)
\li ...
\endlist
\raw HTML
<hr />
<h2>Member Function Documentation</h2>
<h3>void MyObsoleteFunction ()</h3>
<p>Use MyNewFunction() instead.</p>
\endraw
...
\endquotation
\target internal-command
\section1 \\internal
The \\internal command indicates that the referenced
function is not part of the public interface.
The command must stand on its own line.
QDoc ignores the documentation as well as the documented item,
when generating the associated class reference documentation.
\code
/ *!
\internal
Tries to find the decimal separator. If it can't find
it and the thousand delimiter is != '.' it will try to
find a '.';
* /
int QDoubleSpinBoxPrivate::findDelimiter
(const QString &str, int index) const
{
int dotindex = str.indexOf(delimiter, index);
if (dotindex == -1 && thousand != dot && delimiter != dot)
dotindex = str.indexOf(dot, index);
return dotindex;
}
\endcode
This function will not be included in the documentation.
\target preliminary-command
\section1 \\preliminary
The \\preliminary command is for indicating that a referenced
function is still under development.
The command must stand on its own line.
The \\preliminary command expands to a notification in the
function documentation, and marks the function as preliminary when
it appears in lists.
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\code
/ *!
\preliminary
Returns information about the joining type attributes of the
character (needed for certain languages such as Arabic or
Syriac).
* /
QChar::JoiningType QChar::joiningType() const
{
return QChar::joiningType(ucs);
}
\endcode
QDoc renders this as:
\quotation
\raw HTML
<h3>
<a href="http://doc.qt.io/qt-5/qchar.html#JoiningType-enum">JoiningType</a>
QChar::joiningType() const</h3>
\endraw
\b {This function is under development and
subject to change.}
Returns information about the joining type attributes of the
character (needed for certain languages such as Arabic or
Syriac).
\endquotation
And the function's entry in QChar's list of public functions will be
rendered as:
\quotation
\list
\li ...
\li JoiningType \l {QChar::joiningType()} {joiningType}() const \c (preliminary)
\li ...
\endlist
\endquotation
\target since-command
\section1 \\since
The \\since command tells in which minor release
the associated functionality was added.
\code
/ *!
\since 4.1
Returns an icon for \a standardIcon.
...
\sa standardPixmap()
* /
QIcon QStyle::standardIcon(StandardPixmap standardIcon, const QStyleOption *option, const QWidget *widget) const
{
}
\endcode
QDoc renders this as:
\quotation
\raw HTML
<h3>QIcon QStyle::standardIcon(StandardPixmap standardIcon, const QStyleOption *option, const QWidget *widget) const</h3>
\endraw
421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490
This function was introduced in Qt version 4.1
Returns an icon for \a standardIcon.
...
See also \l {QStyle::standardPixmap()} {standardPixmap()}.
\endquotation
QDoc generates the "Qt" reference from the \l
{25-qdoc-configuration-derivedprojects.html#project} {\c project}
configuration variable. For that reason this reference will change
according to the current documentation project.
See also \l {project}
{\c project}.
*/
/*!
\page 17-qdoc-commands-thread.html
\previouspage Status
\contentspage QDoc Manual
\nextpage Relating Things
\title Thread Support
The thread support commands are for specifying the level of
support for multithreaded programming in a class or function.
There are three levels of support: \c threadsafe, \c reentrant and
\c nonreentrant.
The default is \c nonreentrant which means that the associated
class or function cannot be called by multiple threads. \c
Reentrant and \c threadsafe are levels primarily used for classes.
\c Reentrant means that all the functions in the referenced class
can be called simultaneously by multiple threads, provided that
each invocation of the functions reference unique data. While \c
threadsafe means that all the functions in the referenced class
can be called simultaneously by multiple threads even when each
invocation references shared data.
When a class is marked \l {reentrant-command} {\\reentrant} or \l
{threadsafe-command} {\\threadsafe}, functions in that class can
be marked \c nonreentrant using the \l {nonreentrant-command}
{\\nonreentrant} command.
\section1 Example
\target reentrant-example
\code
\beginqdoc
\class QLocale
\brief The QLocale class converts between numbers and their
string representations in various languages.
\reentrant
\ingroup i18n
\ingroup text
QLocale is initialized with a language/country pair in its
constructor and offers number-to-string and string-to-number
conversion functions similar to those in QString.
...
\nonreentrant
491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560
Sets the global default locale to \a locale. These values are
used when a QLocale object is constructed with no
arguments. If this function is not called, the system's locale
is used.
\warning In a multithreaded application, the default locale
should be set at application startup, before any non-GUI
threads are created.
\sa system(), c()
\endqdoc
void QLocale::setDefault(const QLocale &locale)
{
default_d = locale.d;
}
\endcode
QDoc renders this as:
\quotation
\raw HTML
<h1><center>QLocale Class Reference</center></h1>
\endraw
The QLocale class converts between numbers and their string
representations in various languages. More...
\code
#include <QLocale>
\endcode
\b {Note:} All the functions in this class are \l
{17-qdoc-commands-thread.html#reentrant} {reentrant}, except \l
{QLocale::setDefault()} {setDefault()}.
...
\raw HTML
<hr />
<h2>Member Type Documentation</h2>
\endraw
...
\raw HTML
<h3>void QLocale::setDefault ( const QLocale & locale ) </h3>
\endraw
Sets the global default locale to locale. These values are
used when a QLocale object is constructed with no
arguments. If this function is not called, the system's locale
is used.
\warning In a multithreaded application, the default locale
should be set at application startup, before any non-GUI
threads are created.
\warning This function is not reentrant.
See also \l {QLocale::system()} {system()} and \l
{QLocale::c()} {c()}.
...
\endquotation
As shown above, QDoc generates a notification when a class is
declared reentrant, and lists the exceptions (the declared
nonreentrant functions). A link to the general documentation on \l
{17-qdoc-commands-thread.html#reentrant} {reentrancy and thread-safety} is
included. In addition a warning, "\b Warning: This function is
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not reentrant.", is generated in the nonreentrant functions'
documentation.
QDoc will generate the same notification and warnings when a class
is declared threadsafe.
For more information see the general documentation on \l
{17-qdoc-commands-thread.html#reentrant} {reentrancy and thread-safety}.
\section1 Commands
\target threadsafe-command
\section2 \\threadsafe
The \\threadsafe command includes a line in the documentation to
indicate that the associated class or function is \e threadsafe
and can be called simultaneously by multiple threads, even when
separate invocations reference shared data.
The command must stand on its own line.
The documentation generated from this command will be similar to
the what is generated for the \l {reentrant-command} {\\reentrant}
command. See the example above in the \l {reentrant-example}
{introduction}.
See also \l{reentrant-command} {\\reentrant} and
\l{nonreentrant-command} {\\nonreentrant}.
\target reentrant-command
\section2 \\reentrant
The \\reentrant command indicates that the associated class or
function can be called simultaneously by multiple threads,
provided that each invocation references its own data. See the \l
{reentrant-example} {example} above.
The command must stand on its own line.
See also \l{nonreentrant-command} {\\nonreentrant} and
\l{threadsafe-command} {\\threadsafe}.
\target nonreentrant-command
\section2 \\nonreentrant
The \\nonreentrant command indicates that the associated class or
function cannot be called by multiple threads. Nonreentrant is the
default case.
The command must stand on its own line.
When a class is marked \l {reentrant-command} {\\reentrant} or \l
{threadsafe-command} {\\threadsafe}, functions in that class can
be marked \c nonreentrant using this command in the \l{fn-command}
{\\fn} comment of the functions to be excluded.
See also \l{reentrant-command} {\\reentrant} and
\l{threadsafe-command} {\\threadsafe}.
*/
/*!
\page 18-qdoc-commands-relating.html
\previouspage Thread Support
\contentspage QDoc Manual
\nextpage Grouping Things
\title Relating Things
The relating commands are for specifying how one documented
element relates to another documented element. Some examples:
631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700
\list
\li This function is an overload of another function.
\li This function is a reimplementation of another function.
\li This typedef is \e related to some class or header file.
\endlist
There is also a command for documenting that a QML type inherits
some other QML type.
\section1 Commands
\target inherits-command
\section2 \\inherits
The \\inherits command is for documenting that one QML type
inherits some other QML type. It must be included in the
inheriting element's \l{qmltype-command}{\\qmltype} comment.
The argument is the name of the inherited QML type.
\code
/ *!
\qmltype PauseAnimation
\instantiates QDeclarativePauseAnimation
\ingroup qml-animation-transition
\since 4.7
\inherits Animation
\brief The PauseAnimation element provides a pause for an animation.
When used in a SequentialAnimation, PauseAnimation is a step
when nothing happens, for a specified duration.
A 500ms animation sequence, with a 100ms pause between two animations:
SequentialAnimation {
NumberAnimation { ... duration: 200 }
PauseAnimation { duration: 100 }
NumberAnimation { ... duration: 200 }
}
\sa {QML Animation and Transitions}, {declarative/animation/basics}{Animation basics example}
* /
\endcode
QDoc includes this line on the reference page for the
\l{http://qt-project.org/doc/qt-4.7/qml-pauseanimation.html} {PauseAnimation}
element:
\quotation
Inherits \l{http://qt-project.org/doc/qt-4.7/qml-animation.html} {Animation}
\endquotation
\target overload-command
\section2 \\overload
The \\overload command is for indicating that a function is a
secondary overload of its name.
The command must stand on its own line.
For a function name that is overloaded (except constructors), QDoc
expects one primary version of the function, and all the others
marked with the \b {\\overload command}. The primary version
should be fully documented. Each overload can have whatever extra
documentation you want to add for just that overloaded version.
From Qt 4.5, you can include the function name plus '()' as a
parameter to the \b{\\overload} command, which will include a
standard \e{This function overloads...} line of text with a link
to the documentation for the primary version of the function.
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\code
/ *!
\overload addAction()
This convenience function creates a new action with an
\a icon and some \a text. The function adds the newly
created action to the menu's list of actions, and
returns it.
\sa QWidget::addAction()
* /
QAction *QMenu::addAction(const QIcon &icon, const QString &text)
{
QAction *ret = new QAction(icon, text, this);
addAction(ret);
return ret;
}
\endcode
QDoc renders this as:
\quotation
\raw HTML
<h3><a href="http://doc.qt.io/qt-5/qaction.html">QAction</a>
* QMenu::addAction ( const QIcon & <i>icon</i>,
const QString & <i>text</i> )
</h3>
\endraw
This function overloads \l {QMenu::addAction()} {addAction()}
This convenience function creates a new action with an
\e icon and some \e text. The function adds the newly
created action to the menu's list of actions, and
returns it.
See also
\l {QWidget::addAction()} {QWidget::addAction}().
\endquotation
If you don't include the function name with the \b{\\overload}
command, then instead of the "This function overloads..." line
with the link to the documentation for the primary version, you
get the old standard line:
\quotation
This is an overloaded member function, provided for
convenience.
\endquotation.
\target reimp-command
\section2 \\reimp
The \\reimp command is for indicating that a function is a
reimplementation of a virtual function.
The command must stand on its own line.
QDoc will omit the reimplemented function from the class
reference.
\code
/ *!
\reimp
* /
void QToolButton::nextCheckState()
{
Q_D(QToolButton);
if (!d->defaultAction)
QAbstractButton::nextCheckState();
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else
d->defaultAction->trigger();
}
\endcode
This function will not be included in the documentation. Instead,
a link to the base function QAbstractButton::nextCheckState() will
appear in the documentation.
\target relates-command
\section2 \\relates
The \\relates command is for including the documentation of a
global element to some class or header file. The argument is a
class name or header file.
\code
/ *!
\relates QChar
Reads a char from the stream \a in into char \a chr.
\sa {Format of the QDataStream operators}
* /
QDataStream &operator>>(QDataStream &in, QChar &chr)
{
quint16 u;
in >> u;
chr.unicode() = ushort(u);
return in;
}
\endcode
The documentation for this function will be included on the reference page
for class QChar.
*/
/*!
\page 19-qdoc-commands-grouping.html
\previouspage Relating Things
\contentspage QDoc Manual
\nextpage Naming Things
\title Grouping Things
The grouping commands relate classes to defined groups and
modules. The groups are used when generating lists of related
classes in the documentation, while the modules are elements of
Qt's structure.
\section1 Commands
\target ingroup-command
\section2 \\ingroup
The \\ingroup command indicates that the given
overview or documented class belongs to a certain group of
related docmentation.
A class or overview may belong to many groups.
The \\ingroup command's argument is a group name, but note
that the command considers the rest of the line as part of
its argument. Make sure that the group name is followed by
a linebreak.
\code
/ *!
\class QDir
\brief The QDir class provides access to directory
841842843844845846847848849850851852853854855856857858859860861862863864865866867868869870871872873874875876877878879880881882883884885886887888889890891892893894895896897898899900901902903904905906907908909910
structures and their contents.
\ingroup io
...
* /
\endcode
This will include the QDir class in the \c io group, which means,
for example, that QDir will appear on the list created by calling
the \l {group-command} {\\group} command with the \c io argument.
To list overviews that are related to a certain group, you must
generate the list explicitly using the \l {generatelist-command}
{\\generatelist} command with the \c related argument.
See also \l {group-command} {\\group}.
\target inmodule-command
\section2 \\inmodule
The \\inmodule command relates a class to the module specified by
the command's argument.
For the basic classes in Qt, a class's module is determined by its
location, namely its directory. However, for extensions like
ActiveQt and Qt Designer, a class must be related to a module
explicitly.
The command's argument is a module name, but note that the command
considers the rest of the line as part of its argument. Make sure
that the module name is followed by a linebreak.
\code
/*!
\class QDesignerTaskMenuExtension
\inmodule QtDesigner
* /
\endcode
This ensures that the QDesignerTaskMenuExtension class is included
in the Qt Designer module, which means, for example, that the
class will appear on the list created by calling the \l
{generatelist-command} {\\generatelist} command with the \c
{{classesbymodule QtDesigner}} argument.
See also \l {module-command} {\\module} and \l
{generatelist-command} {\\generatelist}.
*/
/*!
\page 20-qdoc-commands-namingthings.html
\previouspage Grouping Things
\contentspage QDoc Manual
\nextpage Markup Commands
\title Naming Things
In general, a title command considers everything that follows it
until the first line break as its argument. If the title is so
long it must span multiple lines, end each line (except the last
one) with a backslash.
\section1 Commands
\target title-command
\section2 \\title
The \\title command sets the title for a documentation page, or
allows you to override it.
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\code
/ *!
\page signalandslots.html
\title Signals & Slots
Signals and slots are used for communication between
objects. The signals and slots mechanism is a central
feature of Qt, and probably the part that differs most
from the features provided by other frameworks.
...
* /
\endcode
QDoc renders this as:
\quotation
\raw HTML
<h1><center>Signal and Slots</center></h1>
\endraw
Signals and slots are used for communication between
objects. The signals and slots mechanism is a central
feature of Qt and probably the part that differs most
from the features provided by other frameworks.
...
\endquotation
See also \l {subtitle-command} {\\subtitle}.
\target subtitle-command
\section2 \\subtitle
The \\subtitle command sets a subtitle for a documentation page.
\code
\beginqdoc
\page qtopiacore-overview.html
\title Qtopia Core
\subtitle Qt for Embedded Linux
Qt/Embedded, the embedded Linux port of Qt, is a
complete and self-contained C++ GUI and platform
development tool for Linux-based embedded development.
...
\endqdoc
\endcode
QDoc renders this as:
\quotation
\raw HTML
<h1><center>Qtopia Core</center></h1>
<h2><center>Qt for Embedded Linux</center></h2>
\endraw
Qt/Embedded, the embedded Linux port of Qt, is a
complete and self-contained C++ GUI and platform
development tool for Linux-based embedded development.
...
\endquotation
See also \l {title-command} {\\title}.
*/