std:: tuple_element <std::array>
From cppreference.com
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Defined in header
<array>
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||
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template
<
std::
size_t
I,
class
T,
std::
size_t
N
>
struct tuple_element < I, std:: array < T, N > > ; |
(since C++11) | |
Provides compile-time indexed access to the type of the elements of the array using tuple-like interface.
Member types
| Member type | Definition |
| type | the type of elements of the array |
Possible implementation
template<std::size_t I, class T> struct tuple_element; template<std::size_t I, class T, std::size_t N> struct tuple_element<I, std::array<T,N>> { using type = T; }; |
Example
Run this code
#include <array> #include <tuple> #include <type_traits> int main() { // define array and get the type of the element at position 0 std::array<int, 10> data{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}; using T = std::tuple_element<0, decltype(data)>::type; // int static_assert(std::is_same_v<T, int>); const auto const_data = data; using CT = std::tuple_element<0, decltype(const_data)>::type; // const int // the result of tuple_element depends on the cv-qualification of the tuple-like type static_assert(!std::is_same_v<T, CT>); static_assert(std::is_same_v<CT, const int>); }
See also
| Structured binding (C++17) | binds the specified names to sub-objects or tuple elements of the initializer |
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(C++11)
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obtains the type of the specified element
(class template specialization) |
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(C++11)
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obtains the type of the elements of
pair
(class template specialization) |