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std::is_compound

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Revision as of 17:45, 2 November 2012 by P12bot (Talk | contribs)

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

<td>
Defined in header <type_traits>
</td>

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

<tr class="t-dcl ">

<td >
template< class T >
struct is_compound;
</td>

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

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.

Contents

Inherited from std::integral_constant

Member constants

value
[static]
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>

Notes

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

Possible implementation

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

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

See also

checks if a type is fundamental type
(class template) [edit]
(C++11)
checks if a type is scalar type
(class template) [edit]
(C++11)
checks if a type is object type
(class template) [edit]
(C++11)
checks if a type is an array type
(class template) [edit]