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#include <iostream>
#include <typeinfo>
 
#include <type_traits>
#include <bits/range_access.h>
 
/* comment the following line and everything is fine... */
#define nsp
 
#ifdef nsp
namespace test
{
#endif
 
 
namespace detail
{
	// To allow ADL with custom begin/end
	using std::begin;
	using std::end;
 
	template <typename T>
	auto is_iterable_impl(int)
	-> decltype (
	    begin(std::declval<T&>()) != end(std::declval<T&>()), // begin/end and operator !=
	    ++std::declval<decltype(begin(std::declval<T&>()))&>(), // operator ++
	    *begin(std::declval<T&>()), // operator*
	    std::true_type {});
 
	template <typename T>
	std::false_type is_iterable_impl(...);
 
}
 
template <typename T>
using is_iterable = decltype(detail::is_iterable_impl<T>(0));
 
 
 
 
 
template <typename T,typename _F>
inline typename std::enable_if< is_iterable<T>::value >::type
for_all_ele(T&& arr,_F&& fn)
{
	for(auto &x:arr)
		for_all_ele(x,fn);
 
}
 
template <typename T,typename _F>
inline typename std::enable_if< not is_iterable<T>::value >::type
for_all_ele(T&& x,_F&& fn)
{
	fn(x);
}
 
 
 
#ifdef nsp
}
using namespace test;
#endif
 
 
 
 
#include <iostream>
using namespace std;
 
int main()
{
	int x[2][5]= {1,2,5,68,9,12,35,6,32,89};
 
	for_all_ele(x,[](int &xij){	cout<<xij<<",";	});
 
	return 0;
}
 
 
 
 
 
 
 
 
 
 
 

prog.cpp: In instantiation of 'typename std::enable_if<decltype (is_iterable_impl<T>(0))::value>::type test::for_all_ele(T&&, _F&&) [with T = int (&)[5]; _F = main()::<lambda(int&)>&; typename std::enable_if<decltype (is_iterable_impl<T>(0))::value>::type = void]':
prog.cpp:47:14:   required from 'typename std::enable_if<decltype (is_iterable_impl<T>(0))::value>::type test::for_all_ele(T&&, _F&&) [with T = int (&)[2][5]; _F = main()::<lambda(int&)>; typename std::enable_if<decltype (is_iterable_impl<T>(0))::value>::type = void]'
prog.cpp:75:47:   required from here
prog.cpp:47:14: error: no matching function for call to 'for_all_ele(int&, main()::<lambda(int&)>&)'
   for_all_ele(x,fn);
              ^
prog.cpp:44:1: note: candidate: template<class T, class _F> typename std::enable_if<decltype (is_iterable_impl<T>(0))::value>::type test::for_all_ele(T&&, _F&&)
 for_all_ele(T&& arr,_F&& fn)
 ^
prog.cpp:44:1: note:   template argument deduction/substitution failed:
prog.cpp: In substitution of 'template<class T, class _F> typename std::enable_if<decltype (is_iterable_impl<T>(0))::value>::type test::for_all_ele(T&&, _F&&) [with T = int&; _F = main()::<lambda(int&)>&]':
prog.cpp:47:14:   recursively required from 'typename std::enable_if<decltype (is_iterable_impl<T>(0))::value>::type test::for_all_ele(T&&, _F&&) [with T = int (&)[5]; _F = main()::<lambda(int&)>&; typename std::enable_if<decltype (is_iterable_impl<T>(0))::value>::type = void]'
prog.cpp:47:14:   required from 'typename std::enable_if<decltype (is_iterable_impl<T>(0))::value>::type test::for_all_ele(T&&, _F&&) [with T = int (&)[2][5]; _F = main()::<lambda(int&)>; typename std::enable_if<decltype (is_iterable_impl<T>(0))::value>::type = void]'
prog.cpp:75:47:   required from here
prog.cpp:44:1: error: no type named 'type' in 'struct std::enable_if<false, void>'

Standard output is empty