| 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::function_collection */ |
| 10 | |
| 11 | #include <boost/poly_collection/function_collection.hpp> |
| 12 | #include <functional> |
| 13 | #include <memory> |
| 14 | #include <random> |
| 15 | #include <vector> |
| 16 | #include "rolegame.hpp" |
| 17 | |
| 18 | int main() |
| 19 | { |
| 20 | //[basic_function_1 |
| 21 | std::vector<std::unique_ptr<sprite>> sprs; |
| 22 | std::vector<std::string> msgs; |
| 23 | std::vector<window> wnds; |
| 24 | //] |
| 25 | |
| 26 | // populate sprs |
| 27 | std::mt19937 gen{92748}; // some arbitrary random seed |
| 28 | std::discrete_distribution<> rnd{{1,1,1}}; |
| 29 | for(int i=0;i<4;++i){ // assign each type with 1/3 probability |
| 30 | switch(rnd(gen)){ |
| 31 | case 0: sprs.push_back(x: std::make_unique<warrior>(args&: i));;break; |
| 32 | case 1: sprs.push_back(x: std::make_unique<juggernaut>(args&: i));break; |
| 33 | case 2: sprs.push_back(x: std::make_unique<goblin>(args&: i));break; |
| 34 | } |
| 35 | } |
| 36 | |
| 37 | // populate msgs |
| 38 | msgs.push_back(x: "\"stamina: 10,000\""); |
| 39 | msgs.push_back(x: "\"game over\""); |
| 40 | |
| 41 | // populate wnds |
| 42 | wnds.emplace_back(args: "pop-up 1"); |
| 43 | wnds.emplace_back(args: "pop-up 2"); |
| 44 | |
| 45 | //[basic_function_2 |
| 46 | //= #include <boost/poly_collection/function_collection.hpp> |
| 47 | //= ... |
| 48 | //= |
| 49 | // function signature accepting std::ostream& and returning nothing |
| 50 | using render_callback=void(std::ostream&); |
| 51 | |
| 52 | boost::function_collection<render_callback> c; |
| 53 | //] |
| 54 | |
| 55 | //[basic_function_3 |
| 56 | //<- |
| 57 | auto render_sprite=[](const sprite& s){ |
| 58 | //-> |
| 59 | //= auto render_sprite(const sprite& s){ |
| 60 | return [&](std::ostream& os){s.render(os);}; |
| 61 | }/*<-*/;/*->*/ |
| 62 | |
| 63 | //<- |
| 64 | auto render_message=[](const std::string& m){ |
| 65 | //-> |
| 66 | //= auto render_message(const std::string& m){ |
| 67 | return [&](std::ostream& os){os<<m;}; |
| 68 | }/*<-*/;/*->*/ |
| 69 | |
| 70 | //<- |
| 71 | auto render_window=[](const window& w){ |
| 72 | //-> |
| 73 | //= auto render_window(const window& w){ |
| 74 | return [&](std::ostream& os){w.display(os);}; |
| 75 | }/*<-*/;/*->*/ |
| 76 | //= ... |
| 77 | //= |
| 78 | for(const auto& ps:sprs)c.insert(x: render_sprite(*ps)); |
| 79 | for(const auto& m:msgs)c.insert(x: render_message(m)); |
| 80 | for(const auto& w:wnds)c.insert(x: render_window(w)); |
| 81 | //] |
| 82 | |
| 83 | //[basic_function_4 |
| 84 | const char* comma=""; |
| 85 | for(const auto& cbk:c){ |
| 86 | std::cout<<comma; |
| 87 | cbk(std::cout); |
| 88 | comma=","; |
| 89 | } |
| 90 | std::cout<<"\n"; |
| 91 | //] |
| 92 | |
| 93 | //[basic_function_5 |
| 94 | auto cbk=*c.begin(); |
| 95 | cbk(std::cout); // renders first element to std::cout |
| 96 | std::function<render_callback> f=cbk; |
| 97 | f(std::cout); // exactly the same |
| 98 | //] |
| 99 | |
| 100 | //[basic_function_6 |
| 101 | //= *c.begin()=render_message("last minute message"); // compile-time error |
| 102 | //] |
| 103 | } |
| 104 |