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#include <iostream>
#include <mutex>
#include <functional>
#include <future>
#include <thread>
#include <chrono>
#include <random>
 
/** /
template<class R>
R Semaphore(const std::function<R(void)>& F) {
	static std::mutex M;
	std::lock_guard<std::mutex> L(M);
	return F();
}/**/
template<class R,class... Arg>
R Semaphore(const std::function<R(Arg&...)>& F,const Arg& ...A) {// a good semaphoe.but compile.
	static std::mutex M;
	std::lock_guard<std::mutex> L(M);
	return F(A...);
}/**/
template<class R>
R Semaphore2(const std::function<R(void)>& F,std::mutex M) {
//	static std::mutex M;
	std::lock_guard<std::mutex> L(M);
	return F();
}
/**/
int main() {
	std::mutex M;
	std::mt19937 Rnd;
	std::uniform_int_distribution<> U(-3, 3);
	/** /
	for (std::size_t i = 0; i < 128; i++) {
	auto F = [i]()->bool {std::cout << i << std::endl; return true; };
	Semaphore<bool>(F);
	}
	/**/
	for (std::size_t i = 0; i < 12800; i++) {
		auto F = [i]()->bool {std::cout << i << std::endl; return true; };
	//	Semaphore<bool>(F);
	//	auto FU = std::async(std::launch::async, Semaphore<bool>, F);//compiler cant solve to some of same name functions issue.
		auto FU = std::async(std::launch::async, Semaphore<bool>, F,10);//compiler cant solve template argements issue.
		//	auto FU = std::async(std::launch::async, [F]() {return Semaphore(F); });//why not...
	//	auto FU = std::async(std::launch::async, [](auto F) {Semaphore<bool>(F); 	std::this_thread::sleep_for(std::chrono::nanoseconds(3)); return true; }, F);
		//	auto FU = std::async(std::launch::async, [i]() {std::cout << i << std::endl; });//why not...
		//	auto FU = std::async(std::launch::async, [](auto i) {std::cout << i << std::endl; },i);//why not...
	//	auto FU = std::async(std::launch::async, [](auto F,auto R) {Semaphore<bool>(F); 	std::this_thread::sleep_for(std::chrono::milliseconds(R)); return true; }, F,U(Rnd));
	}
	std::this_thread::sleep_for(std::chrono::seconds(3));
	return 0;
}

prog.cpp: In function ‘int main()’:
prog.cpp:43:65: error: no matching function for call to ‘async(std::launch, <unresolved overloaded function type>, main()::<lambda()>&, int)’
   auto FU = std::async(std::launch::async, Semaphore<bool>, F,10);//compiler cant solve template argements issue.
                                                                 ^
In file included from prog.cpp:4:
/usr/include/c++/8/future:1712:5: note: candidate: ‘template<class _Fn, class ... _Args> std::future<typename std::result_of<typename std::decay<_Tp>::type(typename std::decay<_Args>::type ...)>::type> std::async(std::launch, _Fn&&, _Args&& ...)’
     async(launch __policy, _Fn&& __fn, _Args&&... __args)
     ^~~~~
/usr/include/c++/8/future:1712:5: note:   template argument deduction/substitution failed:
/usr/include/c++/8/future: In substitution of ‘template<class _Fn, class ... _Args> std::future<typename std::result_of<typename std::decay<_Tp>::type(typename std::decay<_Args>::type ...)>::type> std::async(std::launch, _Fn&&, _Args&& ...) [with _Fn = bool (&)(const std::function<bool()>&); _Args = {main()::<lambda()>&, int}]’:
prog.cpp:43:65:   required from here
/usr/include/c++/8/future:1712:5: error: no type named ‘type’ in ‘class std::result_of<bool (*(main()::<lambda()>, int))(const std::function<bool()>&)>’
/usr/include/c++/8/future:1745:5: note: candidate: ‘template<class _Fn, class ... _Args> std::future<typename std::result_of<typename std::decay<_Tp>::type(typename std::decay<_Args>::type ...)>::type> std::async(_Fn&&, _Args&& ...)’
     async(_Fn&& __fn, _Args&&... __args)
     ^~~~~
/usr/include/c++/8/future:1745:5: note:   template argument deduction/substitution failed:
/usr/include/c++/8/future: In substitution of ‘template<class _Fn, class ... _Args> std::future<typename std::result_of<typename std::decay<_Tp>::type(typename std::decay<_Args>::type ...)>::type> std::async(_Fn&&, _Args&& ...) [with _Fn = std::launch; _Args = {bool (&)(const std::function<bool()>&), main()::<lambda()>&, int}]’:
prog.cpp:43:65:   required from here
/usr/include/c++/8/future:1745:5: error: no type named ‘type’ in ‘class std::result_of<std::launch(bool (*)(const std::function<bool()>&), main()::<lambda()>, int)>’

Standard output is empty