std::meta::make_signed

 

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Const-volatile modifications remove_const remove_volatile remove_cv add_const add_volatile add_cv Reference modifications remove_reference add_lvalue_reference add_rvalue_reference Sign modifications make_signed make_unsigned Array modifications remove_extent remove_all_extents Pointer modifications remove_pointer add_pointer Other transformations remove_cvref decay common_type common_reference underlying_type invoke_result unwrap_reference unwrap_ref_decay tuple_size tuple_element is_applicable_type is_nothrow_applicable_type apply_result variant_size variant_alternative type_order

 

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Defined in header <meta>
consteval std::meta::info make_signed( std::meta::info r );		(since C++26)

Returns a reflection of the corresponding signed type S for integral type T, where T is represented by r.

If T is an integral (except bool) or enumeration type, then S is the signed integer type corresponding to T, with the same cv-qualifiers.

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

If T is an enumeration type or char, wchar_t, char8_t, char16_t, char32_t, then S is the signed integer type with the smallest rank having the same sizeof as T.

Otherwise, the program is ill-formed.

Equivalent to return std::meta::dealias(^^std::make_signed_t<T>);.

Parameters

r

-

a reflection value

Return value

A reflection of the signed type S as described above.

Exceptions

Throws std::meta::exception if r does not represent enumeration or integral (except bool) type or type alias.

Example

Run this code

#include <meta>

enum struct E : unsigned short {};

static_assert
(""
    && (make_signed(^^unsigned char) == ^^signed char)
    && (make_signed(^^unsigned int) == ^^signed int)
    && (make_signed(^^volatile unsigned long) == ^^volatile signed long)
    && (make_signed(^^E) == ^^signed short)
);

int main() {}

See also

is_signed_type (C++26)	checks if reflection represents a signed arithmetic type (function)
is_unsigned_type (C++26)	checks if reflection represents an unsigned arithmetic type (function)
make_unsigned (C++26)	returns the corresponding unsigned type for reflected integral type (function)
make_signed (C++11)	obtains the corresponding signed type for the given integral type (class template)