ceph/src/boost/libs/poly_collection/example/exceptions.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 /* Boost.PolyCollection exceptions */
  10
  11 #include <algorithm>
  12 #include <array>
  13 #include <boost/poly_collection/base_collection.hpp>
  14 #include <random>
  15 #include "rolegame.hpp"
  16
  17 int main()
  18 {
  19   boost::base_collection<sprite> c,c2;
  20
  21   // populate c
  22
  23   std::mt19937                 gen{92748}; // some arbitrary random seed
  24   std::discrete_distribution<> rnd{{1,1,1}};
  25   for(int i=0;i<8;++i){        // assign each type with 1/3 probability
  26     switch(rnd(gen)){
  27       case 0: c.insert(warrior{i});break;
  28       case 1: c.insert(juggernaut{i});break;
  29       case 2: c.insert(goblin{i});break;
  30     }
  31   }
  32
  33   auto render=[](const boost::base_collection<sprite>& c){
  34     const char* comma="";
  35     for(const sprite& s:c){
  36       std::cout<<comma;
  37       s.render(std::cout);
  38       comma=",";
  39     }
  40     std::cout<<"\n";
  41   };
  42   render(c);
  43
  44   try{
  45 //[exceptions_1
  46   c.insert(elf{0}); // no problem
  47 //=  ...
  48 //=
  49   c2=c; // throws boost::poly_collection::not_copy_constructible
  50 //]
  51   }catch(boost::poly_collection::not_copy_constructible&){}
  52
  53   try{
  54 //[exceptions_2
  55   c.clear<elf>(); // get rid of non-copyable elfs
  56   c2=c;           // now it works
  57   // check that the two are indeed equal
  58   std::cout<<(c==c2)<<"\n";
  59                   // throws boost::poly_collection::not_equality_comparable
  60 //]
  61   }catch(boost::poly_collection::not_equality_comparable&){}
  62 }