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std::tuple_size<std::array>

From cppreference.com
< cpp‎ | container‎ | array
 
 
 
 
Defined in header <array>
template< class T, std::size_t N >

struct tuple_size< std::array<T, N> > :
    std::integral_constant<std::size_t, N>

{ };
(since C++11)

Provides access to the number of elements in an std::array as a compile-time constant expression.

Contents

[edit] Helper variable template

template< class T >
inline constexpr std::size_t tuple_size_v = tuple_size<T>::value;
(since C++17)

Inherited from std::integral_constant

Member constants

value
[static]
N, the number of elements in the array
(public static member constant)

Member functions

operator std::size_t
converts the object to std::size_t, returns value
(public member function)
operator()
(C++14)
returns value
(public member function)

Member types

Type Definition
value_type std::size_t
type std::integral_constant<std::size_t, value>

[edit] Example

#include <array>
 
int main()
{
    auto arr = std::to_array("ABBA");
    static_assert(std::tuple_size<decltype(arr)>{} == 5);
}

[edit] See also

Structured binding (C++17) binds the specified names to sub-objects or tuple elements of the initializer[edit]
obtains the number of elements of a tuple-like type
(class template) [edit]
obtains the size of tuple at compile time
(class template specialization) [edit]
obtains the size of a pair
(class template specialization) [edit]
obtains the number of components of a std::ranges::subrange
(class template specialization) [edit]