ceph/src/boost/libs/poly_collection/example/basic_any.cpp

   1 /* Copyright 2016-2017 Joaquin M Lopez Munoz.
   2  * Distributed under the Boost Software License, Version 1.0.
   3  * (See accompanying file LICENSE_1_0.txt or copy at
   4  * http://www.boost.org/LICENSE_1_0.txt)
   5  *
   6  * See http://www.boost.org/libs/poly_collection for library home page.
   7  */
   8
   9 /* basic usage of boost::any_collection */
  10
  11 #include <boost/poly_collection/any_collection.hpp>
  12 #include <boost/type_erasure/operators.hpp>
  13 #include <random>
  14 #include "rolegame.hpp"
  15
  16 //[basic_any_1
  17 std::ostream& operator<<(std::ostream& os,const sprite& s)
  18 {
  19   s.render(os);
  20   return os;
  21 }
  22
  23 // std::string already has a suitable operator<<
  24
  25 std::ostream& operator<<(std::ostream& os,const window& w)
  26 {
  27   w.display(os);
  28   return os;
  29 }
  30 //]
  31
  32 int main()
  33 {
  34 //[basic_any_2
  35 //=  #include <boost/poly_collection/any_collection.hpp>
  36 //=  #include <boost/type_erasure/operators.hpp>
  37 //=  ...
  38 //=
  39   using renderable=boost::type_erasure::ostreamable<>;
  40   boost::any_collection<renderable> c;
  41 //]
  42
  43 //[basic_any_3
  44   // populate with sprites
  45   std::mt19937                 gen{92748}; // some arbitrary random seed
  46   std::discrete_distribution<> rnd{{1,1,1}};
  47   for(int i=0;i<4;++i){        // assign each type with 1/3 probability
  48     switch(rnd(gen)){
  49       case 0: c.insert(warrior{i});break;
  50       case 1: c.insert(juggernaut{i});break;
  51       case 2: c.insert(goblin{i});break;
  52     }
  53   }
  54
  55   // populate with messages
  56   c.insert(std::string{"\"stamina: 10,000\""});
  57   c.insert(std::string{"\"game over\""});
  58
  59   // populate with windows
  60   c.insert(window{"pop-up 1"});
  61   c.insert(window{"pop-up 2"});
  62 //]
  63
  64
  65 //[basic_any_4
  66   const char* comma="";
  67   for(const auto& r:c){
  68     std::cout<<comma<<r;
  69     comma=",";
  70   }
  71   std::cout<<"\n";
  72 //]
  73 }