std::tuple_size<std::array>
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std::array
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tuple_size<std::array>
Deduction guides (C++17)
Defined in header
<array>
template< class T, std::size_t N >
(since C++11)
struct tuple_size< std::array <T, N> > :
std::integral_constant <std::size_t, N>
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 >
constexpr std::size_t tuple_size_v = tuple_size<T>::value;
(since C++17)
constexpr std::size_t tuple_size_v = tuple_size<T>::value;
Inherited from std::integral_constant
Member constants
value
[static]
N, the number of elements in the array (public static member constant)
Member functions
operator()
(C++14)
(public member function)
Member types
Type
Definition
value_type
std::size_t
type
std::integral_constant <std::size_t, value>
[edit] Example
Run this code
#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]
(C++11)
a tuple
(class template specialization) [edit]