Hi, Christohe Thanks for quick reply. On Tue, 21 Jun 2011 21:09:20 +0200 "Christophe Henry" <christophe.j.henry@googlemail.com> wrote:
Hello,
On Boost.Msm 1.46.1, When I use explicit entries and entry pseudo states, I have to provide a template argument "region id". http://www.boost.org/doc/libs/1_46_1/libs/msm/doc/HTML/ch03s02.html#d0e930
But I couldn't find documents about numbering policy of region id. I also check the example below. http://www.boost.org/doc/libs/1_46_1/libs/msm/doc/HTML/examples/DirectEntryT... The example passes the region id 0 and 1. I'd like to know how to decide which region is 0(or1).
Am I missing something?
Thanks, Takatoshi
Hi,
The region ids are numbered in the order of the initial_state typedef:
typedef boost::mpl::vector<Start1,Start2> initial_state;
Start1 will be the initial state of the first region (id 0), Start2 the initial state of the second region (id 1).
Thanks, I understand. I believe if I pass the out of range value then compile error should occur. And I tested. 0 and 1 are OK. (expected) -1 is NG. (expected) But 2 is OK. (unexpected) 3 or more is NG. (expected) I'm not expert of msm's implementation. I suspect that state_machine.hpp:(2256) BOOST_STATIC_ASSERT(find_region_id<typename StateType::wrapped_entry>::region_index <= nr_regions::value); should be BOOST_STATIC_ASSERT(find_region_id<typename StateType::wrapped_entry>::region_index < nr_regions::value);
Alternatively, you can omit the id and let MSM build a graph using mpl_graph and find this out for you (which will work if your pseudo entry is somehow connected to the initial state). Please note however that there is a compile-time cost for this.
Great!! This is the function that I really want to.
HTH, Christophe
P.S.We met BoosoCon2010, how are you? Regards, Takatoshi