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#include <iostream>
#include <vector>
#include <functional>
 
template<class InputIterator, class Function>
Function my_for_each(InputIterator first, InputIterator last, Function fn)
{
	while (first != last) {
		fn(*first);
		++first;
	}
	return fn;  
}
 
struct FunctorNMC //non-move-constructible
{
	FunctorNMC() = default;
	FunctorNMC(FunctorNMC&&) = delete;
 
	void operator()(int a) const { std::cout << a << " ";	}
};
 
void print(int a) { std::cout << a << " "; }
 
int main()
{
	std::vector<int> v{1,2,3};
 
	auto lambda = [](int a){ std::cout << a << " "; };
	std::function<void(int)> func = lambda;
 
	//my_for_each(v.begin(), v.end(), FunctorNMC());
	std::cout << "\n";
 
	FunctorNMC tmp;
	my_for_each(v.begin(), v.end(), tmp);
 
	std::cout << "\n";
	my_for_each(v.begin(), v.end(), lambda);
	std::cout << "\n";
	my_for_each(v.begin(), v.end(), func);
	std::cout << "\n";
	my_for_each(v.begin(), v.end(), print);
	std::cout << "\n";
}

prog.cpp: In function ‘int main()’:
prog.cpp:36:37: error: use of deleted function ‘constexpr FunctorNMC::FunctorNMC(const FunctorNMC&)’
  my_for_each(v.begin(), v.end(), tmp);
                                     ^
prog.cpp:15:8: note: ‘constexpr FunctorNMC::FunctorNMC(const FunctorNMC&)’ is implicitly declared as deleted because ‘FunctorNMC’ declares a move constructor or move assignment operator
 struct FunctorNMC //non-move-constructible
        ^
prog.cpp:6:10: error:   initializing argument 3 of ‘Function my_for_each(InputIterator, InputIterator, Function) [with InputIterator = __gnu_cxx::__normal_iterator<int*, std::vector<int> >; Function = FunctorNMC]’
 Function my_for_each(InputIterator first, InputIterator last, Function fn)
          ^
prog.cpp: In instantiation of ‘Function my_for_each(InputIterator, InputIterator, Function) [with InputIterator = __gnu_cxx::__normal_iterator<int*, std::vector<int> >; Function = FunctorNMC]’:
prog.cpp:36:37:   required from here
prog.cpp:12:9: error: use of deleted function ‘FunctorNMC::FunctorNMC(FunctorNMC&&)’
  return fn;  
         ^
prog.cpp:18:2: error: declared here
  FunctorNMC(FunctorNMC&&) = delete;
  ^

Standard output is empty