std::is_signed
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<metanoindex/>
<tbody> </tbody>| definiert in Header <type_traits>
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template< class T > struct is_signed; |
(seit C++11) | |
Wenn
T ein signiertes arithmetischen Typ ist, stellt das Mitglied konstanten value gleich true. Für jede andere Art, value ist false .Original:
If
T is a signed arithmetic type, provides the member constant value equal true. For any other type, value is false.The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
You can help to correct and verify the translation. Click here for instructions.
Inherited from std::integral_constant
Member constants
value [statisch] |
true wenn T is a signed arithmetic type , false anders Original: true if T is a signed arithmetic type , false otherwise The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (public static Mitglied konstanten) |
Member functions
operator bool |
wandelt das Objekt bool, gibt value Original: converts the object to bool, returns value The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (öffentliche Elementfunktion) |
Member types
Type
Original: Type The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. |
Definition |
value_type
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bool
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type
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std::integral_constant<bool, value>
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Beispiel
#include <iostream>
#include <type_traits>
class A {};
enum B : int {};
enum class C : int {};
int main()
{
std::cout << std::boolalpha;
std::cout << std::is_signed<A>::value << '\n';
std::cout << std::is_signed<float>::value << '\n';
std::cout << std::is_signed<signed int>::value << '\n';
std::cout << std::is_signed<unsigned int>::value << '\n';
std::cout << std::is_signed<B>::value << '\n';
std::cout << std::is_signed<C>::value << '\n';
}
Output:
false
true
true
false
false
false
