state_machine

c++ template DSL style impl state_machine

features

• header only
• C++11 or later
• formly defined state machine in DSL style
• decouple state machine define and implementation

usage

1- include state_machine.h in your source file

#include "state_machine.h" 

2- define all states and trigger events for transitions, we use a struct/class to define an event, so it can bring data/parameters for the transition

enum class State {
    S1,
    S2,
}

struct E1 {
};

struct E2 {
};

3- define the state machine derived from state_machine<T,S>

struct MyFsm : state_machine<MySM, State::S1> {
};

the second param is the init state of your state machine.

4- add transtion handling functions for each event and state pair, the virtual functions on_undefed_act ,on_default_act will be invoked if no transition is defined for the current state and event.

    void do_pay( int state_, const put& evt_ ) { std::cout << "do pay" << std::endl; }
    void do_pack( int state_, const paied& evt_ ) { std::cout << "do pack" << std::endl; }
    void do_reload( int state_, const cont& evt_ ) { std::cout << "do reload" << std::endl; }

define the transition table at the end of the class definition.

    TRANSITIONS( _T( st::init, put, st::payment, &order_processor::do_pay ),
                 _T( st::payment, paied, st::packing ),  //!! will use default
                 _T( st::shipped, cont, st::init, &order_processor::do_reload ) );

example and unittest

example.cpp

author

wechat:371536435 email:[email protected]