std::make_unsigned

 

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Defined in header <type_traits>
template< class T > struct make_unsigned;		(since C++11)

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

If T is signed or unsigned char, short, int, long, long long; the unsigned type from this list corresponding to T is provided.

If T is an enumeration type or char, wchar_t, char8_t (since C++20), char16_t, char32_t; the unsigned integer type with the smallest rank having the same sizeof as T is provided.

Otherwise, the behavior is undefined.	(until C++20)
Otherwise, the program is ill-formed.	(since C++20)

The behavior of a program that adds specializations for std::make_unsigned is undefined.

Member types

Name	Definition
type	the unsigned integer type corresponding to T

Helper types

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

Example

Run this code

#include <type_traits>
 
int main()
{
    using uchar_type = std::make_unsigned_t<char>;
    using uint_type  = std::make_unsigned_t<int>;
    using ulong_type = std::make_unsigned_t<volatile long>;
 
    static_assert(
        std::is_same_v<uchar_type, unsigned char> and
        std::is_same_v<uint_type, unsigned int> and
        std::is_same_v<ulong_type, volatile unsigned long>
    );
}

See also

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