std::is_array - cppreference.com

From cppreference.com

template<classT>structis_array;(since C++11)std::is_array is a

UnaryTypeTrait

.

Checks whether T is an array type. Provides the member constant value which is equal to true, if T is an array type. Otherwise, value is equal to false.

If the program adds specializations for std::is_array or std::is_array_v, the behavior is undefined.

Template parameters

T - a type to check Helper variable template

template<classT>constexprboolis_array_v=is_array<T>::value;(since C++17)Inherited from

std::integral_constant

Member constants

value

[static]

true if T is an array type, false otherwise
(public static member constant)Member functions

operator bool

converts the object to bool, returns value
(public member function)operator()

(C++14)

returns value
(public member function)Member types

Type Definition value_typebooltypestd::integral_constant<bool,value>Possible implementation

template<classT>structis_array:std::false_type{};template<classT>structis_array<T[]>:std::true_type{};template<classT,std::size_tN>structis_array<T[N]>:std::true_type{};Example

Run this code

#include<array>#include<type_traits>classA{};static_assert(std::is_array<A>::value==false);static_assert(std::is_array<A[]>::value==true);static_assert(std::is_array<A[3]>::value==true);static_assert(std::is_array<float>::value==false);static_assert(std::is_array<int>::value==false);static_assert(std::is_array<int[]>::value==true);static_assert(std::is_array<int[3]>::value==true);static_assert(std::is_array<std::array<int,3>>::value==false);intmain(){}See also

is_bounded_array

(C++20)

checks if a type is an array type of known bound
(class template)

[edit]

is_unbounded_array

(C++20)

checks if a type is an array type of unknown bound
(class template)

[edit]

rank

(C++11)

obtains the number of dimensions of an array type
(class template)

[edit]

extent

(C++11)

obtains the size of an array type along a specified dimension
(class template)

[edit]

remove_extent

(C++11)

removes one extent from the given array type
(class template)

[edit]

remove_all_extents

(C++11)

removes all extents from the given array type
(class template)

[edit]

is_array_type

(C++26)

checks if reflected type is an array type
(function)

[edit]