struct member_offset { ptrdiff_t bytes; ptrdiff_t bits; constexpr ptrdiff_t total_bits() const; auto operator<=>(const member_offset&) const = default; }; constexpr ptrdiff_t member_offset::total_bits() const;

Returns: bytes * CHAR_BIT + bits.

consteval member_offset offset_of(info r);

Let V be the offset in bits from the beginning of a complete object of the type represented by parent_of(r) to the subobject associated with the construct represented by r.

Returns: {V / CHAR_BIT, V % CHAR_BIT}.

Throws: meta​::​exception unless r represents a non-static data member, unnamed bit-field, or direct base class relationship for which either B is not a virtual base class or D is not an abstract class.

consteval size_t size_of(info r);

Otherwise, size_of(type_of(r)).

Throws: meta​::​exception unless all of the following conditions are met:

• dealias(r) is a reflection of a type, object, value, variable of non-reference type, non-static data member that is not a bit-field, direct base class relationship, or data member description ([class.mem.general]) where W is ⊥.

• If dealias(r) represents a type, then is_complete_type(r) is true.

consteval size_t alignment_of(info r);

Returns:

• If dealias(r) represents a type T, then alignment_of(add_pointer(r)) if T is a reference type and the alignment requirement of T otherwise.

• Otherwise, if dealias(r) represents a variable or object, then the alignment requirement of the variable or object.

• Otherwise, if r represents a direct base class relationship, then alignment_of(type_of(r)).

• Otherwise, if r represents a non-static data member M of a class C, then the alignment of the direct member subobject corresponding to M of a complete object of type C.

• Otherwise, r represents a data member description ([class.mem.general]).

  If A is not ⊥, then the value A.

  Otherwise, alignment_of(^^T).

Throws: meta​::​exception unless all of the following conditions are met:

• dealias(r) is a reflection of a type, object, variable of non-reference type, non-static data member that is not a bit-field, direct base class relationship, or data member description ([class.mem.general]) where W is ⊥.

• If dealias(r) represents a type, then is_complete_type(r) is true.

consteval size_t bit_size_of(info r);

Returns:

• If r represents an unnamed bit-field or a non-static data member that is a bit-field with width W, then W.

• Otherwise, if r represents a data member description ([class.mem.general]) and W is not ⊥, then W.

• Otherwise, CHAR_BIT * size_of(r).

Throws: meta​::​exception unless all of the following conditions are met:

• dealias(r) is a reflection of a type, object, value, variable of non-reference type, non-static data member, unnamed bit-field, direct base class relationship, or data member description.

• If dealias(r) represents a type, then is_complete_type(r) is true.