is_const-Klasse
Testet, ob Typ const ist.
template<class Ty>
struct is_const;
Parameter
- Ty
Der Typ in Abfragen.
Hinweise
Eine Instanz der Typprädikatgriffe true, wenn Tyconst-qualified ist.
Beispiel
// std_tr1__type_traits__is_const.cpp
// compile with: /EHsc
#include <type_traits>
#include <iostream>
struct trivial
{
int val;
};
int main()
{
std::cout << "is_const<trivial> == " << std::boolalpha
<< std::is_const<trivial>::value << std::endl;
std::cout << "is_const<const trivial> == " << std::boolalpha
<< std::is_const<const trivial>::value << std::endl;
std::cout << "is_const<int> == " << std::boolalpha
<< std::is_const<int>::value << std::endl;
std::cout << "is_const<const int> == " << std::boolalpha
<< std::is_const<const int>::value << std::endl;
return (0);
}
Anforderungen
Header: <type_traits>
Namespace: std