std::is_compound

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Defined in header `<type_traits>`

template< class T > struct is_compound;		(C++11 feature)

If T is a compound type (that is, array, function, object pointer, function pointer, member object pointer, member function pointer, reference, class, union, or enumeration, including any cv-qualified variants), provides the member constant value equal true. For any other type, value is false.

Inherited from std::integral_constant

Member constants


`value`	true if `T` is a compound type , false otherwise (public static member constant)

Member functions


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

Member types


Type	Definition

`value_type`	`bool`

`type`	std::integral_constant<bool, value>

[edit] Notes

Compound types are the types that are constructed from fundamental types. Any C++ type is either fundamental or compound.

[edit] Equivalent definition

template< class T >
struct is_compound : std::integral_constant<bool, !std::is_fundamental<T>::value> {};

[edit] Example

#include <iostream>
#include <type_traits>
 
int main() {
    class cls {};
    std::cout << (std::is_compound<cls>::value
                     ? "T is compound"
                     : "T is not a compound") << '\n';
    std::cout << (std::is_compound<int>::value
                     ? "T is compound"
                     : "T is not a compound") << '\n';
}

Output:

T is compound
T is not a compound

[edit] See also

is_fundamental (C++11)

checks if a type is fundamental type
(class template)

is_scalar (C++11)

checks if a type is scalar type
(class template)

is_object (C++11)

checks if a type is object type
(class template)

is_array (C++11)

checks if a type is an array type
(class template)