std::make_signed (3) Linux Manual Page

std::make_signed – std::make_signed

Synopsis

Defined in header<type_traits>

    template <class T>
    (since C++ 11)

        struct make_signed;

If T is an integral (except bool) or enumeration type, provides the member typedef type which is the signed integer type corresponding to T, with the same cv-qualifiers.
Otherwise, the behavior is undefined.

Member types

Name Definition
type the signed integer type corresponding to T

Helper types

template< class T > (since C++14)
using make_signed_t = typename make_signed<T>::type;

Example

// Run this code

#include <iostream>

#include <type_traits>
int main()
{
    typedef std::make_signed<unsigned char>::type char_type;
    typedef std::make_signed<unsigned int>::type int_type;
    typedef std::make_signed<volatile unsigned long>::type long_type;
    bool ok1 = std::is_same<char_type, signed char>::value;
    bool ok2 = std::is_same<int_type, signed int>::value;
    bool ok3 = std::is_same<long_type, volatile signed long>::value;
    std::cout << std::boolalpha
              << "char_type is 'signed char'?          : " << ok1 << '\n'
              << "int_type  is 'signed int'?           : " << ok2 << '\n'
              << "long_type is 'volatile signed long'? : " << ok3 << '\n';
}

Output:

  char_type is ‘signed char’? : true
  int_type is ‘signed int’? : true
  long_type is ‘volatile signed long’? : true

See also

is_signed checks if a type is a signed arithmetic type
              (class template)
(C++11)
is_unsigned checks if a type is an unsigned arithmetic type
              (class template)
(C++11)
make_unsigned makes the given integral type unsigned
              (class template)
(C++11)