fork(1) download

#include <type_traits>
#include <array>
 
template <bool...> struct bools {};
 
template <bool... bs>
using all_of = ::std::is_same<bools<true, bs...>, bools<bs..., true>>;
 
template<typename... Ts>
using contains_only_array_of_3_int =
	all_of<::std::is_same<::std::array<int, 3>, Ts>::value...>;
 
template <std::size_t V>
class Test
{
public:
	Test() {}
 
	template <typename... TArgs>
	Test(TArgs&& ... args) 
	{
		static_assert(sizeof...(TArgs) == V, "arguments count mismatch");
		static_assert(contains_only_array_of_3_int<::std::decay_t<TArgs>...>::value,
		              "arguments type mismatch");
	}
};
 
int main()
{
	::std::array<int, 3> a{ 1, 2, 3 };
	Test<1> t
	{
		::std::array<int, 3>{ 1, 2, 3 }
	};
	Test<2> t2
	{
		::std::array<int, 3>{ 1, 2, 3 }
	,	::std::array<int, 3>{ 4, 5, 6 }
	};
	Test<3> t3
	{
		a
	,	::std::array<int, 3>{ 4, 5, 6 }
	,	::std::array<int, 3>{ 7, 8, 9 }
	};
	Test<3> t3_args_count_fail
	{
		::std::array<int, 3>{ 1, 2, 3 }
	,	::std::array<int, 3>{ 4, 5, 6 }
	};
	Test<3> t3_args_tupe_fail
	{
		::std::array<int, 3>{ 1, 2, 3 }
	,	::std::array<int, 2>{ 4, 5 }
	,	::std::array<int, 3>{ 7, 8, 9 }
	};
	return(0);
}
 

prog.cpp: In instantiation of ‘Test<V>::Test(TArgs&& ...) [with TArgs = {std::array<int, 3ul>, std::array<int, 3ul>}; long unsigned int V = 3ul]’:
prog.cpp:50:2:   required from here
prog.cpp:22:3: error: static assertion failed: arguments count mismatch
   static_assert(sizeof...(TArgs) == V, "arguments count mismatch");
   ^~~~~~~~~~~~~
prog.cpp: In instantiation of ‘Test<V>::Test(TArgs&& ...) [with TArgs = {std::array<int, 3ul>, std::array<int, 2ul>, std::array<int, 3ul>}; long unsigned int V = 3ul]’:
prog.cpp:56:2:   required from here
prog.cpp:23:3: error: static assertion failed: arguments type mismatch
   static_assert(contains_only_array_of_3_int<::std::decay_t<TArgs>...>::value,
   ^~~~~~~~~~~~~

Standard output is empty