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

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&.


[edit] Parameters

args - zero or more arguments to construct the tuple from

[edit] Return value

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

[edit] 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::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)...);

[edit] Example

#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";


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

[edit] See also

creates a tuple of lvalue references or unpacks a tuple into individual objects
(function template) [edit]
creates a tuple of forwarding references
(function template) [edit]
creates a tuple by concatenating any number of tuples
(function template) [edit]
calls a function with a tuple of arguments
(function template) [edit]