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Showing content from https://en.cppreference.com/w/cpp/language/../error/error_code/../../utility/make_from_tuple.html below:

std::make_from_tuple - cppreference.com

template< class T, class Tuple >
constexpr T make_from_tuple( Tuple&& t );

template< class T, tuple-like Tuple >
constexpr T make_from_tuple( Tuple&& t );

Construct an object of type T, using the elements of the tuple t as the arguments to the constructor.

Given the exposition-only function /*make-from-tuple-impl*/ defined as follows:
template<class T, tuple-like Tuple, std::size_t... I> // no constraint on Tuple before C++23
constexpr T /*make-from-tuple-impl*/(Tuple&& t, std::index_sequence<I...>)
{
    return T(std::get<I>(std::forward<Tuple>(t))...);
}

The effect is equivalent to:
return /*make-from-tuple-impl*/<T>(
    std::forward<Tuple>(t),
    std::make_index_sequence<std::tuple_size_v<std::remove_reference_t<Tuple>>>{}
);.

If

• std::is_constructible_v<T, decltype(std::get<I>(std::declval<Tuple>()))...> is false,

the program is ill-formed.

The constructed T object or reference.

Due to guaranteed copy elision, T need not be movable.

#include <iostream>
#include <tuple>
 
struct Foo
{
    Foo(int first, float second, int third)
    {
        std::cout << first << ", " << second << ", " << third << '\n';
    }
};
 
int main()
{
    auto tuple = std::make_tuple(42, 3.14f, 0);
    std::make_from_tuple<Foo>(std::move(tuple));
}

Output:

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

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