std::get(std::tuple)

From cppreference.com
< cpp‎ | utility‎ | tuple
(1)
template< std::size_t I, class... Types >

typename std::tuple_element<I, tuple<Types...> >::type&

    get( tuple<Types...>& t );
(since C++11)
(until C++14)
template< std::size_t I, class... Types >

constexpr std::tuple_element_t<I, tuple<Types...> >&

    get( tuple<Types...>& t );
(since C++14)
(2)
template< std::size_t I, class... Types >

typename std::tuple_element<I, tuple<Types...> >::type&&

    get( tuple<Types...>&& t );
(since C++11)
(until C++14)
template< std::size_t I, class... Types >

constexpr std::tuple_element_t<I, tuple<Types...> >&&

    get( tuple<Types...>&& t );
(since C++14)
(3)
template< std::size_t I, class... Types >

typename std::tuple_element<I, tuple<Types...> >::type const&

    get( const tuple<Types...>& t );
(since C++11)
(until C++14)
template< std::size_t I, class... Types >

constexpr std::tuple_element_t<I, tuple<Types...> >const&

    get( const tuple<Types...>& t );
(since C++14)
template< std::size_t I, class... Types >

constexpr std::tuple_element_t<I, tuple<Types...> >const&&

    get( const tuple<Types...>&& t );
(4) (since C++17)
template< class T, class... Types >
constexpr T& get(tuple<Types...>& t);
(5) (since C++14)
template< class T, class... Types >
constexpr T&& get(tuple<Types...>&& t);
(6) (since C++14)
template< class T, class... Types >
constexpr const T& get(const tuple<Types...>& t);
(7) (since C++14)
template< class T, class... Types >
constexpr const T&& get(const tuple<Types...>&& t);
(8) (since C++17)
1-4) Extracts the Ith element from the tuple. I is an integer value in [0, sizeof...(Types)).
5-8) Extracts the element of the tuple t whose type is T. Fails to compile if the tuple has more than one element of that type.

Parameters

t - tuple whose contents to extract

Return value

A reference to the selected element of t.

Exceptions

noexcept specification:  
noexcept