std::is_unsigned

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is_unsigned
(C++11)
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Defined in header <type_traits>
template< class T >
struct is_unsigned;
(since C++11)

If T is an unsigned arithmetic type, 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 an unsigned arithmetic 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>

[edit] Example

#include <iostream>
#include <type_traits>
 
class A {};
enum B : unsigned {};
enum class C : unsigned {};
 
int main() 
{
    std::cout << std::boolalpha;
    std::cout << std::is_unsigned<A>::value << '\n';
    std::cout << std::is_unsigned<float>::value << '\n';
    std::cout << std::is_unsigned<signed int>::value << '\n';
    std::cout << std::is_unsigned<unsigned int>::value << '\n';
    std::cout << std::is_unsigned<B>::value << '\n';
    std::cout << std::is_unsigned<C>::value << '\n';
}

Output:

false
false
false
true
false
false

[edit] See also

(C++11)
checks if a type is signed arithmetic type
(class template)
checks if a type is floating-point type
(class template)
(C++11)
checks if a type is integral type
(class template)
(C++11)
makes the given integral type signed
(class template)
makes the given integral type unsigned
(class template)