Re: [Boost-users] [MSM] Boost.MSM: statemachine to transition on templatized event-type

29 May 2015

      Hi,
...
having tested Boost.MSM, I'm pretty happy with it.
:)
...
It's interesting, in that it seems to handle all states in a static table.
No "new" operator etc.
It's much faster without dynamic allocation.

<snip>

    g_row,
...
Unfortunately
gcc gives this error:
d.cpp:119:5: error: ‘g_row’ was not declared in this scope
    g_row,
Short answer. Try:

typename Machine_<EventT>::template g_row

Long answer: g_row is a type of state_machine_def and as your fsm is a
template, it becomes a dependent type (=> typename) and a template one even
(=> template).

C++ is sometimes really annoying :(

Longer answer. Give up this front-end, it's deprecated anyway. A better
solution will be:

#include 
using namespace boost::msm::front;

struct GuardToOdd
  {
      template 
      bool operator()(EVT const& num,FSM& ,SourceState& ,TargetState& )
      {
          const long long x = static_cast<long long>(num.getNum());
          return ((x == num.getNum()) // is Integral type
                  && ((x % 2) != 0));
      }
  };

Row< StateFloat,   EventT, StateOdd, none, GuardToOdd>

HTH,
Christophe

Re: [Boost-users] [MSM] Boost.MSM: statemachine to transition on templatized event-type

Christophe Henry