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+/****************************************************************************
+**
+** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:FDL$
+** GNU Free Documentation License
+** 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.
+**
+** 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.
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+ \example statemachine/factorial
+ \title Factorial States Example
+
+ The Factorial States example shows how to use \l{The State Machine
+ Framework} to calculate the factorial of an integer.
+
+ The statechart for calculating the factorial looks as follows:
+
+ \image factorial-example.png
+ \omit
+ \caption This is a caption
+ \endomit
+
+ In other words, the state machine calculates the factorial of 6 and prints
+ the result.
+
+ \snippet statemachine/factorial/main.cpp 0
+
+ The Factorial class is used to hold the data of the computation, \c x and
+ \c fac. It also provides a signal that's emitted whenever the value of \c
+ x changes.
+
+ \snippet statemachine/factorial/main.cpp 1
+
+ The FactorialLoopTransition class implements the guard (\c x > 1) and
+ calculations (\c fac = \c x * \c fac; \c x = \c x - 1) of the factorial
+ loop.
+
+ \snippet statemachine/factorial/main.cpp 2
+
+ The FactorialDoneTransition class implements the guard (\c x <= 1) that
+ terminates the factorial computation. It also prints the final result to
+ standard output.
+
+ \snippet statemachine/factorial/main.cpp 3
+
+ The application's main() function first creates the application object, a
+ Factorial object and a state machine.
+
+ \snippet statemachine/factorial/main.cpp 4
+
+ The \c compute state is created, and the initial values of \c x and \c fac
+ are defined. A FactorialLoopTransition object is created and added to the
+ state.
+
+ \snippet statemachine/factorial/main.cpp 5
+
+ A final state, \c done, is created, and a FactorialDoneTransition object
+ is created with \c done as its target state. The transition is then added
+ to the \c compute state.
+
+ \snippet statemachine/factorial/main.cpp 6
+
+ The machine's initial state is set to be the \c compute state. We connect
+ the QStateMachine::finished() signal to the QCoreApplication::quit() slot,
+ so the application will quit when the state machine's work is
+ done. Finally, the state machine is started, and the application's event
+ loop is entered.
+
+ */