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Showing content from https://en.cppreference.com/w/cpp/language/../memory/weak_ptr/../../utility/tuple/make_tuple.html below:

std::make_tuple - cppreference.com

Creates a tuple object, deducing the target type from the types of arguments.

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&.

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

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::decay<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::forward<Types>(args)...);
}

#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

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