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/* Copyright 2016-2017 Joaquin M Lopez Munoz.
* Distributed under the Boost Software License, Version 1.0.
* (See accompanying file LICENSE_1_0.txt or copy at
* http://www.boost.org/LICENSE_1_0.txt)
*
* See http://www.boost.org/libs/poly_collection for library home page.
*/
/* basic usage of boost::function_collection */
#include <boost/poly_collection/function_collection.hpp>
#include <functional>
#include <memory>
#include <random>
#include <vector>
#include "rolegame.hpp"
int main()
{
//[basic_function_1
std::vector<std::unique_ptr<sprite>> sprs;
std::vector<std::string> msgs;
std::vector<window> wnds;
//]
// populate sprs
std::mt19937 gen{92748}; // some arbitrary random seed
std::discrete_distribution<> rnd{{1,1,1}};
for(int i=0;i<4;++i){ // assign each type with 1/3 probability
switch(rnd(gen)){
case 0: sprs.push_back(std::make_unique<warrior>(i));;break;
case 1: sprs.push_back(std::make_unique<juggernaut>(i));break;
case 2: sprs.push_back(std::make_unique<goblin>(i));break;
}
}
// populate msgs
msgs.push_back("\"stamina: 10,000\"");
msgs.push_back("\"game over\"");
// populate wnds
wnds.emplace_back("pop-up 1");
wnds.emplace_back("pop-up 2");
//[basic_function_2
//= #include <boost/poly_collection/function_collection.hpp>
//= ...
//=
// function signature accepting std::ostream& and returning nothing
using render_callback=void(std::ostream&);
boost::function_collection<render_callback> c;
//]
//[basic_function_3
//<-
auto render_sprite=[](const sprite& s){
//->
//= auto render_sprite(const sprite& s){
return [&](std::ostream& os){s.render(os);};
}/*<-*/;/*->*/
//<-
auto render_message=[](const std::string& m){
//->
//= auto render_message(const std::string& m){
return [&](std::ostream& os){os<<m;};
}/*<-*/;/*->*/
//<-
auto render_window=[](const window& w){
//->
//= auto render_window(const window& w){
return [&](std::ostream& os){w.display(os);};
}/*<-*/;/*->*/
//= ...
//=
for(const auto& ps:sprs)c.insert(render_sprite(*ps));
for(const auto& m:msgs)c.insert(render_message(m));
for(const auto& w:wnds)c.insert(render_window(w));
//]
//[basic_function_4
const char* comma="";
for(const auto& cbk:c){
std::cout<<comma;
cbk(std::cout);
comma=",";
}
std::cout<<"\n";
//]
//[basic_function_5
auto cbk=*c.begin();
cbk(std::cout); // renders first element to std::cout
std::function<render_callback> f=cbk;
f(std::cout); // exactly the same
//]
//[basic_function_6
//= *c.begin()=render_message("last minute message"); // compile-time error
//]
}
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