<xstd/ints/type_traits/make_unsigned.hpp>

xstd::make_unsigned, xstd::make_unsigned_t

template<class T>
struct make_unsigned;

template<class T>
using make_unsigned_t = typename make_unsigned<T>::type;

The unsigned counterpart of an integral, enumeration or integer-class type.

Member types

Type	Definition
type	the unsigned counterpart of T, where it has one, as below

• For a cv-unqualified integral or enumeration type other than bool, the member type is std::make_unsigned_t<T>.
• For a cv-unqualified type that models integer_class, is not std::integral and is unsigned, type is T.
• For a cv-qualified T whose unqualified type has a member type, type is that with the same qualifiers. A cv-qualified type takes no other path, so it has a member type exactly when its unqualified type does.
• Otherwise there is no member type, so make_unsigned_t<T> is a substitution failure where std::make_unsigned_t<T> would be a hard error: bool, double, int*, complex<double> and void have none.

Remarks

A program may specialize it for the signed half of an integer-class pair, as the ext headers do.

Notes

Every signed exact-width type maps to a type modelling unsigned_integer.

See also

Entity	Relation
make_signed	the other direction
make_unsigned<signed _BitInt(N)>	the bit-precise specializations
integer	asks that the two be mutually inverse
boost::int128, absl::int128	the ext headers' specializations
std::make_unsigned	the standard trait it extends