libs/msm/doc/HTML/examples/ActivateStateBeforeTransitionEuml.cpp
// Copyright 2010 Christophe Henry
// henry UNDERSCORE christophe AT hotmail DOT com
// This is an extended version of the state machine available in the boost::mpl library
// Distributed under the same license as the original.
// Copyright for the original version:
// Copyright 2005 David Abrahams and Aleksey Gurtovoy. Distributed
// under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
#include <iostream>
#include <boost/msm/back/state_machine.hpp>
#include <boost/msm/front/state_machine_def.hpp>
#include <boost/msm/front/euml/euml.hpp>
using namespace std;
namespace msm = boost::msm;
namespace mpl = boost::mpl;
using namespace boost::msm::front::euml;
namespace // Concrete FSM implementation
{
// events
BOOST_MSM_EUML_EVENT(connect)
BOOST_MSM_EUML_EVENT(disconnect)
// flag
BOOST_MSM_EUML_FLAG(is_connected)
BOOST_MSM_EUML_ACTION(SignalConnect)
{
template <class FSM,class EVT,class SourceState,class TargetState>
void operator()(EVT const& ,FSM& fsm,SourceState& ,TargetState& )
{
// by default, this would be wrong (shows false)
cout << "SignalConnect. Connected? "
<< std::boolalpha
<< fsm.template is_flag_active<BOOST_MSM_EUML_FLAG_NAME(is_connected)>() << endl;
}
};
BOOST_MSM_EUML_ACTION(SignalDisconnect)
{
template <class FSM,class EVT,class SourceState,class TargetState>
void operator()(EVT const& ,FSM& fsm,SourceState& ,TargetState& )
{
// by default, this would be wrong (shows true)
cout << "SignalDisconnect. Connected? "
<< std::boolalpha
<< fsm.template is_flag_active<BOOST_MSM_EUML_FLAG_NAME(is_connected)>()
<< endl;
}
};
// The list of FSM states
BOOST_MSM_EUML_ACTION(Connected_Entry)
{
template <class Event,class FSM,class STATE>
void operator()(Event const&,FSM&,STATE& )
{
std::cout << "entering: Connected" << std::endl;
}
};
BOOST_MSM_EUML_ACTION(Connected_Exit)
{
template <class Event,class FSM,class STATE>
void operator()(Event const&,FSM&,STATE& )
{
std::cout << "leaving: Connected" << std::endl;
}
};
BOOST_MSM_EUML_STATE(( Connected_Entry,Connected_Exit,
attributes_ << no_attributes_,
configure_<< is_connected ),Connected)
BOOST_MSM_EUML_ACTION(Disconnected_Entry)
{
template <class Event,class FSM,class STATE>
void operator()(Event const&,FSM&,STATE& )
{
std::cout << "entering: Disconnected" << std::endl;
}
};
BOOST_MSM_EUML_ACTION(Disconnected_Exit)
{
template <class Event,class FSM,class STATE>
void operator()(Event const&,FSM&,STATE& )
{
std::cout << "leaving: Disconnected" << std::endl;
}
};
BOOST_MSM_EUML_STATE(( Disconnected_Entry,Disconnected_Exit ),Disconnected)
// replaces the old transition table
BOOST_MSM_EUML_TRANSITION_TABLE((
Disconnected == Connected + disconnect / SignalDisconnect ,
Connected == Disconnected + connect / SignalConnect
// +------------------------------------------------------------------------------+
),transition_table)
BOOST_MSM_EUML_ACTION(Log_No_Transition)
{
template <class FSM,class Event>
void operator()(Event const& e,FSM&,int state)
{
std::cout << "no transition from state " << state
<< " on event " << typeid(e).name() << std::endl;
}
};
// create a state machine "on the fly"
BOOST_MSM_EUML_DECLARE_STATE_MACHINE(( transition_table, //STT
init_ << Disconnected, // Init State
no_action, // Entry
no_action, // Exit
attributes_ << no_attributes_, // Attributes
configure_ << switch_active_before_transition, // configuration
Log_No_Transition // no_transition handler
),
Connection_) //fsm name
typedef msm::back::state_machine<Connection_> Connection;
void test()
{
Connection connection;
// needed to start the highest-level SM. This will call on_entry and mark the start of the SM
connection.start();
// signal a connection
connection.process_event(connect);
// signal a disconnection
connection.process_event(disconnect);
connection.stop();
}
}
int main()
{
test();
return 0;
}