ceph/src/boost/libs/msm/doc/PDF/examples/iPodSearchEuml.cpp

   1 // Copyright 2010 Christophe Henry
   2 // henry UNDERSCORE christophe AT hotmail DOT com
   3 // This is an extended version of the state machine available in the boost::mpl library
   4 // Distributed under the same license as the original.
   5 // Copyright for the original version:
   6 // Copyright 2005 David Abrahams and Aleksey Gurtovoy. Distributed
   7 // under the Boost Software License, Version 1.0. (See accompanying
   8 // file LICENSE_1_0.txt or copy at
   9 // http://www.boost.org/LICENSE_1_0.txt)
  10
  11 // same as iPodSearch.cpp but using eUML
  12 // requires boost >= v1.40 because using mpl::string
  13
  14 #include <vector>
  15 #include <iostream>
  16
  17 #include <boost/msm/back/state_machine.hpp>
  18 #include <boost/msm/front/euml/euml.hpp>
  19 #include <boost/msm/front/euml/stl.hpp>
  20
  21 using namespace std;
  22 using namespace boost::msm::front::euml;
  23 namespace msm = boost::msm;
  24 namespace mpl = boost::mpl;
  25
  26 // how long the timer will ring when countdown elapsed.
  27 #define RINGING_TIME 5
  28
  29 namespace  // Concrete FSM implementation
  30 {
  31     // events
  32     BOOST_MSM_EUML_DECLARE_ATTRIBUTE(std::string,m_song)
  33     BOOST_MSM_EUML_ATTRIBUTES((attributes_ << m_song ), OneSongDef)
  34     struct OneSong_impl : euml_event<OneSong_impl>,OneSongDef
  35     {
  36         OneSong_impl(){}
  37         OneSong_impl(const string& asong)
  38         {
  39             get_attribute(m_song)=asong;
  40         }
  41         OneSong_impl(const char* asong)
  42         {
  43             get_attribute(m_song)=asong;
  44         }
  45         OneSong_impl(const OneSong_impl& asong)
  46         {
  47             get_attribute(m_song)=asong.get_attribute(m_song);
  48         }
  49         const string& get_data() const {return get_attribute(m_song);}
  50     };
  51     OneSong_impl const OneSong;
  52
  53     // attribute definitions
  54     BOOST_MSM_EUML_DECLARE_ATTRIBUTE(vector<OneSong_impl>,m_src_container)
  55     BOOST_MSM_EUML_DECLARE_ATTRIBUTE(vector<OneSong_impl>,m_tgt_container)
  56     BOOST_MSM_EUML_DECLARE_ATTRIBUTE(std::string,m_letters)
  57     BOOST_MSM_EUML_DECLARE_ATTRIBUTE(vector<OneSong_impl>::iterator,m_src_it)
  58
  59     // the same attribute name can be reused
  60     BOOST_MSM_EUML_ATTRIBUTES((attributes_ << m_song ), NotFoundDef)
  61     BOOST_MSM_EUML_EVENT_WITH_ATTRIBUTES(NotFound,NotFoundDef)
  62
  63     BOOST_MSM_EUML_ATTRIBUTES((attributes_ << m_song ), FoundDef)
  64     BOOST_MSM_EUML_EVENT_WITH_ATTRIBUTES(Found,FoundDef)
  65
  66     BOOST_MSM_EUML_EVENT(Done)
  67
  68     // Concrete FSM implementation
  69
  70     // The list of FSM states
  71     BOOST_MSM_EUML_STATE(( (push_back_(fsm_(m_tgt_container),event_(m_song))
  72                             ,process_(Done)),
  73                            no_action ),Insert)
  74
  75     BOOST_MSM_EUML_STATE(( if_then_else_( string_find_(event_(m_song),state_(m_letters)) != Npos_<string>() ,
  76                                           process2_(Found,event_(m_song)),
  77                                           process2_(NotFound,event_(m_song)) ) ,
  78                            no_action,
  79                            attributes_ << m_letters ),StringFind)
  80
  81     BOOST_MSM_EUML_STATE(( if_then_( state_(m_src_it) != end_(fsm_(m_src_container)),
  82                                      process2_(OneSong,*(state_(m_src_it)++)) ),
  83                            no_action,
  84                            attributes_ << m_src_it ),Foreach)
  85
  86     // replaces the old transition table
  87     BOOST_MSM_EUML_TRANSITION_TABLE((
  88           StringFind  == Foreach     + OneSong ,
  89           Insert      == StringFind  + Found  ,
  90           Foreach     == StringFind  + NotFound ,
  91           Foreach     == Insert      + Done
  92           //  +------------------------------------------------------------------------------+
  93           ),transition_table )
  94
  95     BOOST_MSM_EUML_ACTION(Log_No_Transition)
  96     {
  97         template <class FSM,class Event>
  98         void operator()(Event const& e,FSM&,int state)
  99         {
 100             std::cout << "no transition from state " << state
 101                 << " on event " << typeid(e).name() << std::endl;
 102         }
 103     };
 104     // create a state machine "on the fly"
 105     BOOST_MSM_EUML_DECLARE_STATE_MACHINE((     transition_table, //STT
 106                                             init_ << Foreach, // Init
 107                                             (
 108                                             clear_(fsm_(m_src_container)), //clear source
 109                                             clear_(fsm_(m_tgt_container)), //clear results
 110                                             push_back_(fsm_(m_src_container),
 111                                                        String_<mpl::string<'Let ','it ','be'> >()),//add a song
 112                                             push_back_(fsm_(m_src_container),
 113                                                        String_<mpl::string<'Yell','ow s','ubma','rine'> >()),//add a song
 114                                             push_back_(fsm_(m_src_container),
 115                                                        String_<mpl::string<'Twis','t an','d Sh','out'> >()),//add a song
 116                                             push_back_(fsm_(m_src_container),
 117                                                        String_<mpl::string<'She ','love','s yo','u'> >()),//add a song
 118                                             attribute_(substate_(Foreach()),m_src_it)
 119                                                 = begin_(fsm_(m_src_container)) //set the search begin
 120                                             ), // Entry
 121                                             no_action, // Exit
 122                                             attributes_ << m_src_container // song list
 123                                                         << m_tgt_container, // result
 124                                             configure_<< no_configure_,
 125                                             Log_No_Transition
 126                                         ),
 127                                         iPodSearch_) //fsm name
 128
 129
 130     // choice of back-end
 131     typedef msm::back::state_machine<iPodSearch_> iPodSearch;
 132
 133     void test()
 134     {
 135         iPodSearch search;
 136
 137         // look for "She Loves You" using the first letters
 138         search.get_state<BOOST_MSM_EUML_STATE_NAME(StringFind)&>().get_attribute(m_letters)="Sh";// will find 2 songs
 139
 140         // needed to start the highest-level SM. This will call on_entry and mark the start of the SM
 141         search.start();
 142         // display all the songs
 143         for (vector<OneSong_impl>::const_iterator it = search.get_attribute(m_tgt_container).begin();
 144              it != search.get_attribute(m_tgt_container).end();++it)
 145         {
 146             cout << "candidate song:" << (*it).get_attribute(m_song) << endl;
 147         }
 148
 149         cout << "search using more letters" << endl;
 150         // look for "She Loves You" using more letters
 151         search.get_state<BOOST_MSM_EUML_STATE_NAME(StringFind)&>().get_attribute(m_letters)="She";// will find 1 song
 152         search.start();
 153         // display all the songs
 154         for (vector<OneSong_impl>::const_iterator it = search.get_attribute(m_tgt_container).begin();
 155              it != search.get_attribute(m_tgt_container).end();++it)
 156         {
 157             cout << "candidate song:" << (*it).get_attribute(m_song) << endl;
 158         }
 159     }
 160 }
 161
 162 int main()
 163 {
 164     test();
 165     return 0;
 166 }