Christophe Bourez <boost@bourez.be> writes:

I need to maintain a parameter into the state local storage. This parameter is initially contained in the event that causes the transition to the target state. I give hereafter a small illustrative example.

typename sc = boost::statechart;

class EvTest : public sc::event<EvTest> { public: EvTest(std::size_t val) : value(val) {} std::size_t getValue() const { return this->value; } private: std::size_t value; };

class MyStateMachine; class StSource; class StTarget;

class StSource : public sc::simple_state<StSource, MyStateMachine> { public: typedef sc::custom_reaction<EvTest> reactions;

sc::result react(const EvTest &event) { // How to pass event.getValue() to the target state ? transit<StTarget>(); } };

class StTarget : public sc::simple_state<StTarget, MyStateMachine> { public: StTarget(std::size_t val) : val(value) {} private: std::size_t value; };

I have a patch using boost.fusion to allow this. It works this way: class StSource : public sc::simple_state<StSource, MyStateMachine> { public: typedef sc::custom_reaction<EvTest> reactions; sc::result react(const EvTest &event) { // How to pass event.getValue() to the target state ? transit<StTarget>(event.value); // pass arguments to target // state constructor } }; Does Boost have interest in this?

Thanks, Christophe

Regards, -- Felipe Magno de Almeida

Hi Christophe

I need to maintain a parameter into the state local storage. This parameter is initially contained in the event that causes the transition to the target state. I give hereafter a small illustrative example.

The "problem" with passing event data to a constructor of a destination state is hinted at here (item 3): <http://www.boost.org/doc/libs/1_42_0/libs/statechart/doc/future_and_history.html> Nevertheless, the triggering_event() function is available in >=1.42 (but only documented in >=1.43). Also, I'll definitely look at Felipe's patch. HTH, -- Andreas Huber When replying by private email, please remove the words spam and trap from the address shown in the header.