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std::make_tuple(3)	       C++ Standard Libary	      std::make_tuple(3)

NAME
     std::make_tuple - std::make_tuple

Synopsis
	Defined in header <tuple>
	template< class... Types >			      (since C++11)
	std::tuple<VTypes...>  make_tuple(  Types&&... args );	(constexpr since
     C++14)

	Creates a tuple object, deducing the target type from the types of argu-
     ments.

	For each Ti in Types..., the corresponding type Vi in VTypes... is
	std::decay<Ti>::type unless application of std::decay results in
	std::reference_wrapper<X> for some type X, in  which  case  the  deduced
     type is X&.

Parameters
	args - zero or more arguments to construct the tuple from

Return value
	A std::tuple object containing the given values, created as if by
	std::tuple<VTypes...>(std::forward<Types>(t)...).

Possible implementation
	template <class T>
	struct unwrap_refwrapper
	{
	    using type = T;
	};

	template <class T>
	struct unwrap_refwrapper<std::reference_wrapper<T>>
	{
	    using type = T&;
	};

	template <class T>
	using  unwrap_decay_t  =  typename  unwrap_refwrapper<typename	std::de-
     cay<T>::type>::type;
	// or use std::unwrap_ref_decay_t (since C++20)

	template <class... Types>
	constexpr // since C++14
	std::tuple<unwrap_decay_t<Types>...> make_tuple(Types&&... args)
	{
	    return		  std::tuple<unwrap_decay_t<Types>...>(std::for-
     ward<Types>(args)...);
	}

Example
     // Run this code

      #include <iostream>
      #include <tuple>
      #include <functional>

      std::tuple<int, int> f() // this function returns multiple values
      {
	  int x = 5;
	  return std::make_tuple(x, 7); // return {x,7}; in C++17
      }

      int main()
      {
	  // heterogeneous tuple construction
	  int n = 1;
	  auto t = std::make_tuple(10, "Test", 3.14, std::ref(n), n);
	  n = 7;
	  std::cout << "The value of t is ("
		    << std::get<0>(t) << ", "
		    << std::get<1>(t) << ", "
		    << std::get<2>(t) << ", "
		    << std::get<3>(t) << ", "
		    << std::get<4>(t) << ")\n";

	  // function returning multiple values
	  int a, b;
	  std::tie(a, b) = f();
	  std::cout << a << ' ' << b << '\n';
      }

Output:
      The value of t is (10, Test, 3.14, 7, 1)
      5 7

See also
	tie		 creates a tuple of lvalue references or unpacks a tuple
     into
	(C++11) 	 individual objects
			 (function template)
	forward_as_tuple creates a tuple of forwarding references
	(C++11) 	 (function template)
	tuple_cat	 creates a tuple by concatenating any number of tuples
	(C++11) 	 (function template)
	apply		 calls a function with a tuple of arguments
	(C++17) 	 (function template)

http://cppreference.com 	   2024.06.10		      std::make_tuple(3)
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