std::is_object

 

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ptrdiff_t size_t max_align_t (C++11)     byte (C++17)	nullptr_t (C++11) offsetof NULL
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type_info type_index (C++11)	bad_typeid bad_cast

 

Template:ddcl list begin <tr class="t-dsc-header">

<td>

Defined in header <type_traits>

</td>

<td></td> <td></td> </tr> <tr class="t-dcl ">

<td >

template< class T >
struct is_object;

</td>

<td class="t-dcl-nopad"> </td> <td > (since C++11) </td> </tr> Template:ddcl list end

If T is an object type (that is, scalar, array, class, or union), provides the member constant value equal true. For any other type, value is false.

Inherited from std::integral_constant

Member constants

value [static]

true if T is an object 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_type	bool
type	std::integral_constant<bool, value>

Example

Run this code

#include <iostream>
#include <type_traits>
 
int main() {
    class cls {};
    std::cout << std::boolalpha;
    std::cout << std::is_object<int>::value << '\n';
    std::cout << std::is_object<int&>::value << '\n';
    std::cout << std::is_object<cls>::value << '\n';
    std::cout << std::is_object<cls&>::value << '\n';
}

Output:

true
false
true
false

See also

is_scalar (C++11)	checks if a type is a scalar type (class template)
is_array (C++11)	checks if a type is an array type (class template)
is_union (C++11)	checks if a type is a union type (class template)
is_class (C++11)	checks if a type is a non-union class type (class template)