The std::make_signed template of C++ STL is present in the <type_traits> header file. The std::make_signed template of C++ STL is used to get the signed type corresponding to T(Triat class), by keeping any cv-qualifiers. It can be checked using std::is_same::value function whether the given type T is signed type or not.
Header File:
#include<type_traits>
Template Class:
template< class T > struct make_signed; template<class T> using make_signed_t = typename make_signed<T>::type;
Syntax:
std::make_signed<T>::type
Parameter: The template std::make_signed accepts a single parameter T(Trait class) and maked the type T as a signed type.
Below is the program to demonstrate std::make_signed in C++:
Program:
// C++ program to illustrate // std::make_signed // make_signed #include <iostream> #include <type_traits> using namespace std;
// Declare enum enum ENUM1 { a,
b,
c };
enum class ENUM2 : unsigned char { x,
y,
z };
// Driver Code int main()
{ // Declare variable using make_signed
// for int, unsigned, const unsigned,
// enum1 and enum2
typedef make_signed< int >::type A;
typedef make_signed<unsigned>::type B;
typedef make_signed< const unsigned>::type C;
typedef make_signed<ENUM1>::type D;
typedef make_signed<ENUM2>::type E;
cout << boolalpha;
// Check if the above declared variables
// are signed type or not
cout << "A is signed type? "
<< is_same< int , A>::value
<< endl;
cout << "B is signed type? "
<< is_same< int , B>::value
<< endl;
cout << "C is signed type? "
<< is_same< int , C>::value
<< endl;
cout << "D is signed type? "
<< is_same< int , D>::value
<< endl;
cout << "E is signed type? "
<< is_same< int , E>::value
<< endl;
return 0;
} |
A is signed type? true B is signed type? true C is signed type? false D is signed type? true E is signed type? false
Reference: http://www.cplusplus.com/reference/type_traits/make_signed/