boost::any stopped working as Kleene event in 1.86 in boost::msm #87
Description
boost::any starts having compilation errors when used as "Kleene" (any) event (as described in this doc: https://www.boost.org/doc/libs/1_86_0/libs/msm/doc/HTML/ch03s03.html#d0e1392
I basically need to use "const boost::any" and mark "const boost::any" as Kleene event
In version with "boost::any" (non const) (the full code at the end)
struct transition_table : mpl::vector<
msmf::Row<State<1>, Event<3>, State<23>, Action<3>, Guard<false>>,
msmf::Row<State<1>, boost::any, State<23>, Action<303>, Guard<true>>
> {};I have this output when using boost 1.84:
State::entry(1)
State::exit(1)
Action(303)
State::entry(23)
But when switching to 1.86 - the code stops compiling:
g++ -Iboost_1_86_0 .\test.cpp
In file included from boost_1_86_0/boost/msm/back/state_machine.hpp:65,
from .\test.cpp:1:
boost_1_86_0/boost/msm/back/dispatch_table.hpp: In instantiation of 'static boost::msm::back::HandledEnum boost::msm::back::dispatch_table<Fsm, Stt, Event, CompilePolicy>::chain_row<Seq, AnEvent, State>::execute_helper::execute(Fsm&, int, int, Event&, const mpl_::false_&) [with Sequence = boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, Event<3>, State<23>, Action<3>, Guard > >, boost::mpl::vector<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na>, 0>; Seq = boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, Event<3>, State<23>, Action<3>, Guard > >, boost::mpl::vector<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na>, 0>; AnEvent = Event<3>; State = State<1>; Fsm = boost::msm::back::state_machine; Stt = boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, Event<3>, State<23>, Action<3>, Guard > >, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, boost::mpl::vector0<mpl_::na>, 1>, 1>; Event = Event<3>; CompilePolicy = boost::msm::back::favor_runtime_speed; mpl_::false_ = mpl_::bool_]':
boost_1_86_0/boost/msm/back/dispatch_table.hpp:96:57: required from 'static boost::msm::back::HandledEnum boost::msm::back::dispatch_table<Fsm, Stt, Event, CompilePolicy>::chain_row<Seq, AnEvent, State>::execute(Fsm&, int, int, Event&) [with Seq = boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, Event<3>, State<23>, Action<3>, Guard > >, boost::mpl::vector<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na>, 0>; AnEvent = Event<3>; State
= State<1>; Fsm = boost::msm::back::state_machine; Stt = boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, Event<3>, State<23>, Action<3>, Guard > >, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, boost::mpl::vector0<mpl_::na>, 1>, 1>; Event = Event<3>; CompilePolicy = boost::msm::back::favor_runtime_speed]'
boost_1_86_0/boost/msm/back/dispatch_table.hpp:182:50: required from 'typename boost::disable_if<typename boost::is_same<typename Transition::current_state_type, Fsm>::type, void>::type boost::msm::back::dispatch_table<Fsm, Stt, Event, CompilePolicy>::init_cell::init_event_base_case(const Transition&, const mpl_::true_&, const mpl_::false_&) const [with Transition = boost::msm::back::dispatch_table<boost::msm::back::state_machine, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, Event<3>, State<23>, Action<3>,
Guard > >, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, boost::mpl::vector0<mpl_::na>, 1>, 1>, Event<3>, boost::msm::back::favor_runtime_speed>::chain_row<boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, Event<3>, State<23>, Action<3>, Guard > >, boost::mpl::vector<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na>, 0>, Event<3>, State<1> >; Fsm = boost::msm::back::state_machine; Stt = boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, Event<3>, State<23>, Action<3>, Guard > >, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, boost::mpl::vector0<mpl_::na>, 1>, 1>; Event = Event<3>; CompilePolicy = boost::msm::back::favor_runtime_speed; typename boost::disable_if<typename boost::is_same<typename Transition::current_state_type, Fsm>::type, void>::type = void; typename boost::is_same<typename Transition::current_state_type, Fsm>::type = boost::integral_constant<bool, false>; typename Transition::current_state_type = State<1>; mpl_::true_ = mpl_::bool_; mpl_::false_ = mpl_::bool_]'
boost_1_86_0/boost/msm/back/dispatch_table.hpp:268:33: required from 'typename boost::disable_if<typename has_not_real_row_tag::type, void>::type boost::msm::back::dispatch_table<Fsm, Stt, Event, CompilePolicy>::init_cell::operator()(const Transition&, boost::msm::back::dummy<1>) const [with Transition = boost::msm::back::dispatch_table<boost::msm::back::state_machine, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, Event<3>, State<23>, Action<3>, Guard > >, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, boost::mpl::vector0<mpl_::na>, 1>, 1>, Event<3>, boost::msm::back::favor_runtime_speed>::chain_row<boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, Event<3>, State<23>, Action<3>, Guard > >, boost::mpl::vector<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na>, 0>, Event<3>, State<1> >; Fsm = boost::msm::back::state_machine; Stt = boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, Event<3>, State<23>, Action<3>, Guard > >, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, boost::mpl::vector0<mpl_::na>, 1>, 1>; Event = Event<3>; CompilePolicy = boost::msm::back::favor_runtime_speed; typename boost::disable_if<typename has_not_real_row_tag::type, void>::type = void; typename has_not_real_row_tag::type = mpl_::bool_]'
boost_1_86_0/boost/mpl/for_each.hpp:78:26: required from 'static void boost::mpl::aux::for_each_impl::execute(Iterator*, LastIterator*, TransformFunc*, F) [with Iterator = boost::mpl::v_iter<boost::mpl::v_item<boost::msm::back::dispatch_table<boost::msm::back::state_machine, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, Event<3>, State<23>, Action<3>, Guard > >, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, boost::mpl::vector0<mpl_::na>, 1>, 1>, Event<3>, boost::msm::back::favor_runtime_speed>::chain_row<boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, Event<3>, State<23>, Action<3>, Guard > >, boost::mpl::vector<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na>, 0>, Event<3>, State<1> >, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, boost::mpl::vector0<mpl_::na>, 0>, 0>, 1>; LastIterator = boost::mpl::v_iter<boost::mpl::v_item<boost::msm::back::dispatch_table<boost::msm::back::state_machine, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, Event<3>, State<23>, Action<3>, Guard > >, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, boost::mpl::vector0<mpl_::na>, 1>, 1>, Event<3>, boost::msm::back::favor_runtime_speed>::chain_row<boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, Event<3>, State<23>, Action<3>, Guard > >, boost::mpl::vector<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na,
mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na>, 0>, Event<3>, State<1> >, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, boost::mpl::vector0<mpl_::na>, 0>, 0>, 2>; TransformFunc = boost::mpl::identity<mpl_::na>; F = boost::msm::back::dispatch_table<boost::msm::back::state_machine, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, Event<3>, State<23>, Action<3>, Guard > >, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, boost::mpl::vector0<mpl_::na>, 1>, 1>, Event<3>, boost::msm::back::favor_runtime_speed>::init_cell]'
boost_1_86_0/boost/mpl/for_each.hpp:82:22: required from 'static void boost::mpl::aux::for_each_impl::execute(Iterator*, LastIterator*, TransformFunc*, F) [with Iterator = boost::mpl::v_iter<boost::mpl::v_item<boost::msm::back::dispatch_table<boost::msm::back::state_machine, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, Event<3>, State<23>, Action<3>, Guard > >, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, boost::mpl::vector0<mpl_::na>, 1>, 1>, Event<3>, boost::msm::back::favor_runtime_speed>::chain_row<boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, Event<3>, State<23>, Action<3>, Guard > >, boost::mpl::vector<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na>, 0>, Event<3>, State<1> >, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, boost::mpl::vector0<mpl_::na>, 0>, 0>, 0>; LastIterator = boost::mpl::v_iter<boost::mpl::v_item<boost::msm::back::dispatch_table<boost::msm::back::state_machine, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, Event<3>, State<23>, Action<3>, Guard > >, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, boost::mpl::vector0<mpl_::na>, 1>, 1>, Event<3>, boost::msm::back::favor_runtime_speed>::chain_row<boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, Event<3>, State<23>, Action<3>, Guard > >, boost::mpl::vector<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na,
mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na>, 0>, Event<3>, State<1> >, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, boost::mpl::vector0<mpl_::na>, 0>, 0>, 2>; TransformFunc = boost::mpl::identity<mpl_::na>; F = boost::msm::back::dispatch_table<boost::msm::back::state_machine, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, Event<3>, State<23>, Action<3>, Guard > >, boost::mpl::v_item<boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >, boost::mpl::vector0<mpl_::na>, 1>, 1>, Event<3>, boost::msm::back::favor_runtime_speed>::init_cell]'
boost_1_86_0/boost/mpl/for_each.hpp:105:18: [ skipping 5 instantiation contexts, use -ftemplate-backtrace-limit=0 to disable ]
boost_1_86_0/boost/msm/back/state_machine.hpp:2161:49: required from 'void boost::msm::back::state_machine<A0, A1, A2, A3, A4>::region_processing_helper<StateType, typename boost::enable_if<boost::mpl::is_sequence >::type>::process(const Event&) [with Event = Event<3>; StateType = SimpleFront; A0 = SimpleFront; A1 = boost::parameter::void_; A2 = boost::parameter::void_; A3 = boost::parameter::void_; A4 = boost::parameter::void_; typename boost::enable_if<boost::mpl::is_sequence >::type = void; typename StateType::initial_state = boost::mpl::vector<State<1> >]'
boost_1_86_0/boost/msm/back/state_machine.hpp:2224:23: required from 'boost::msm::back::HandledEnum boost::msm::back::state_machine<A0, A1, A2, A3, A4>::do_process_event(const Event&, bool) [with Event = Event<3>; A0 = SimpleFront; A1 = boost::parameter::void_; A2 = boost::parameter::void_; A3 = boost::parameter::void_; A4 = boost::parameter::void_]'
boost_1_86_0/boost/msm/back/state_machine.hpp:1925:42: required from 'boost::msm::back::HandledEnum boost::msm::back::state_machine<A0, A1, A2, A3, A4>::do_process_helper(const EventType&, const mpl_::false_&, bool) [with StateType = Event<3>; EventType = Event<3>; A0 = SimpleFront; A1 = boost::parameter::void_; A2 = boost::parameter::void_; A3 = boost::parameter::void_; A4 = boost::parameter::void_; mpl_::false_ = mpl_::bool_]'
boost_1_86_0/boost/msm/back/state_machine.hpp:2191:65: required from 'boost::msm::back::execute_return boost::msm::back::state_machine<A0, A1, A2, A3, A4>::process_event_internal(const Event&,
boost::msm::back::EventSource) [with Event = Event<3>; A0 = SimpleFront; A1 = boost::parameter::void_; A2 = boost::parameter::void_; A3 = boost::parameter::void_; A4 = boost::parameter::void_; boost::msm::back::execute_return = boost::msm::back::HandledEnum; boost::msm::back::EventSource = unsigned char]'
boost_1_86_0/boost/msm/back/state_machine.hpp:1270:38: required from 'boost::msm::back::execute_return boost::msm::back::state_machine<A0, A1, A2, A3, A4>::process_event(const Event&) [with Event = Event<3>; A0 = SimpleFront; A1 = boost::parameter::void_; A2 = boost::parameter::void_; A3 = boost::parameter::void_; A4 = boost::parameter::void_; boost::msm::back::execute_return = boost::msm::back::HandledEnum]'
.\test.cpp:84:22: required from here
boost_1_86_0/boost/msm/back/dispatch_table.hpp:75:54: error: cannot bind non-const lvalue reference of type 'boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >::transition_event&' {aka 'boost::any&'} to an rvalue of type 'boost::msm::back::state_machine::row_<boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard > >::transition_event' {aka 'boost::any'}
75 | HandledEnum res = first_row::execute(fsm,region_index,state,evt);
| ~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from boost_1_86_0/boost/msm/back/state_machine.hpp:49:
boost_1_86_0/boost/any.hpp:93:9: note: after user-defined conversion: 'boost::any::any(ValueType&&, typename std::enable_if<(! std::is_same<boost::any&, ValueType>::value)>::type*, typename std::enable_if<(! std::is_const<Tp>::value)>::type*) [with ValueType = Event<3>&; typename std::enable_if<(! std::is_same<boost::any&, ValueType>::value)>::type = void; typename std::enable_if<(! std::is_const<Tp>::value)>::type = void]'
93 | any(ValueType&& value
| ^~~
boost_1_86_0/boost/msm/back/state_machine.hpp:437:100: note: initializing argument 4 of 'static boost::msm::back::HandledEnum boost::msm::back::state_machine<A0, A1, A2, A3, A4>::row::execute(boost::msm::back::state_machine<A0, A1, A2, A3, A4>::library_sm&, int, int, transition_event&) [with ROW = boost::msm::front::Row<State<1>, boost::any, State<23>, Action<303>, Guard >; A0 = SimpleFront; A1 = boost::parameter::void; A2 = boost::parameter::void_; A3 = boost::parameter::void_; A4 = boost::parameter::void_; boost::msm::back::state_machine<A0, A1, A2, A3, A4>::library_sm = boost::msm::back::state_machine; transition_event = boost::any]'
437 | static HandledEnum execute(library_sm& fsm, int region_index, int state, transition_event& evt)
|
What helps is to add const next to boost::any in transition_table and mark "const boost::any" as Kleene event,
the code that works now:
#include <boost/msm/back/state_machine.hpp>
#include <boost/msm/front/state_machine_def.hpp>
#include <boost/msm/front/functor_row.hpp>
#include <boost/msm/front/euml/operator.hpp>
#include <boost/any.hpp>
namespace msm = boost::msm;
namespace msmf = msm::front;
namespace msmb = msm::back;
namespace msmfe = boost::msm::front::euml;
namespace mpl = boost::mpl;
template <bool Value>
struct Guard
{
template <typename Event, typename Fsm, typename SourceState, typename TargetState> \
bool operator()(const Event&, Fsm&, SourceState&, TargetState&) \
{
return Value;
}
};
template <int E>
struct Event{};
template <int I>
struct Action
{
template <typename Event, typename Fsm, typename SourceState, typename TargetState>
void operator()(const Event&, Fsm&, SourceState&, TargetState&)
{
std::cout << "Action(" << I << ")" << '\n';
}
};
template <int I>
struct State: msmf::state<>
{
template <typename Event, typename Fsm>
void on_entry(Event&, Fsm&)
{
std::cout << "State::entry(" << I << ")" << '\n';
}
template <typename Event, typename Fsm>
void on_exit(Event&, Fsm&)
{
std::cout << "State::exit(" << I << ")" << '\n';
}
};
template <int I>
struct EndState: msmf::terminate_state<>
{
template <typename Event, typename Fsm>
void on_entry(const Event&, Fsm&)
{
std::cout << "EndState::entry(" << I << ")" << '\n';
}
template <typename Event, typename Fsm>
void on_exit(const Event&, Fsm&)
{
std::cout << "EndState::exit(" << I << ")" << '\n';
}
};
// Since boost_1_86_0 boost::any stopped working as a Kleene event type in boost::msm
// but const boost::any works -- only we need to mark it as a Kleene event type
template<>
struct boost::msm::is_kleene_event<const boost::any>
{
using type = boost::mpl::true_;
};
struct SimpleFront : msmf::state_machine_def<SimpleFront>
{
using Base = msmf::state_machine_def<SimpleFront>;
struct transition_table : mpl::vector<
msmf::Row<State<1>, Event<3>, State<23>, Action<3>, Guard<false>>,
msmf::Row<State<1>, const boost::any, State<23>, Action<303>, Guard<true>>
> {};
using initial_state = boost::mpl::vector<State<1>>;
};
using SimpleImpl = msmb::state_machine<SimpleFront>;
int main() {
SimpleImpl fsm;
fsm.start();
fsm.process_event(Event<3>{});
}