is_const Class
Tests if type is const.
template<class Ty>
struct is_const;
Parameters
- Ty
The type to query.
Remarks
An instance of the type predicate holds true if Ty is const-qualified.
Example
// 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::tr1::is_const<trivial>::value << std::endl;
std::cout << "is_const<const trivial> == " << std::boolalpha
<< std::tr1::is_const<const trivial>::value << std::endl;
std::cout << "is_const<int> == " << std::boolalpha
<< std::tr1::is_const<int>::value << std::endl;
std::cout << "is_const<const int> == " << std::boolalpha
<< std::tr1::is_const<const int>::value << std::endl;
return (0);
}
is_const<trivial> == false is_const<const trivial> == true is_const<int> == false is_const<const int> == true
Requirements
Header: <type_traits>
Namespace: std::tr1