std::get(std::tuple)

 

C++

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template< std::size_t I, class... Types > typename std::tuple_element<I, tuple<Types...> >::type&     get( tuple<Types...>& t );	(1)	(since C++11)
template< std::size_t I, class... Types > typename std::tuple_element<I, tuple<Types...> >::type&&     get( tuple<Types...>&& t );	(2)	(since C++11)
template< std::size_t I, class... Types > typename std::tuple_element<I, tuple<Types...> >::type const&     get( const tuple<Types...>& t );	(3)	(since C++11)

Extracts the Ith element element from the tuple. I is an integer value in [0, sizeof...(Types)).

Parameters

t

-

tuple whose contents to extract

Return value

1) Reference to the Ith element of t.

2) Rvalue reference to the Ith element of t, unless the element is of lvalue reference type, in which case lvalue reference is returned.

3) Const reference to the Ith element of t.

Exceptions

noexcept specification:  

noexcept

  (since C++11)

Example

run this code

#include <iostream>
#include <string>
#include <tuple>
 
int main()
{
    auto t = std::make_tuple(1, "Foo", 3.14);
    std::cout << "(" << std::get<0>(t) << ", " << std::get<1>(t)
              << ", " << std::get<2>(t) << ")\n";
}

Output:

(1, Foo, 3.14)

See also

std::get(std::array)	accesses an element of an array (function template)
std::get(std::pair) (C++11)	accesses an element of a pair (function template)