Defined in header <type_traits> | ||
|---|---|---|
template< class T > struct make_signed; | (since C++11) |
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.
| Name | Definition |
|---|---|
type | the signed integer type corresponding to T |
template< class T > using make_signed_t = typename make_signed<T>::type; | (since C++14) |
#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
|
(C++11) | checks if a type is a signed arithmetic type (class template) |
|
(C++11) | checks if a type is an unsigned arithmetic type (class template) |
|
(C++11) | makes the given integral type unsigned (class template) |
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