Enum Asked 

pub enum Asked<T> {
    NotAsked,
    Asked(T),
}

“Was the question even put?” — the RFC 09 §5.1 O4 split (#246 / P1), made nominal (RFC 13, v1.24).

A generation of report fields spelled “not asked” as Option::None, which conflated it with every other absence the moment a field also had an asked-but-absent reading. This type carries exactly the not-asked distinction and nothing else:

• Asked::NotAsked — the flag was not passed, the sweep was not made, the question does not exist for this subject. On the wire it is absence (the field carries skip_serializing_if + default), byte-identical to the Option it replaced.
• Asked::Asked — the question was put; the payload is the answer, serialized transparently (again exactly as Some did).

The split is the point: a field whose None means asked and nothing was there (an unstamped sample’s age, a producer with no served slice) stays Option — wrapping it here would re-conflate in the other direction.

Variants

NotAsked

The question was not put. Serializes as absence — not zero, not null, not [] (RFC 09 §5.1 O4).

Asked(T)

The question was put, and this is what came back — an empty answer (Asked(vec![]), Asked(0)) is a real answer, distinct from NotAsked on the wire and in the type.

Implementations

impl<T> Asked<T>

pub fn is_not_asked(&self) -> bool

The skip_serializing_if predicate: not-asked is absence.

pub fn is_asked(&self) -> bool

pub fn as_option(&self) -> Option<&T>

The answer, if the question was put.

pub fn into_option(self) -> Option<T>

pub fn as_deref(&self) -> Option<&T::Target>

where T: Deref,

Asked<Vec<T>> → Option<&[T]> and friends, mirroring Option::as_deref.

impl<T: Copy> Asked<T>

pub fn get(&self) -> Option<T>

The answer by value, for Copy payloads.

Trait Implementations

impl<T: Clone> Clone for Asked<T>

fn clone(&self) -> Asked<T>

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T: Copy> Copy for Asked<T>

impl<T: Debug> Debug for Asked<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T> Default for Asked<T>

fn default() -> Asked<T>

Returns the “default value” for a type.

impl<T: Eq> Eq for Asked<T>

impl<T> From<Option<T>> for Asked<T>

Option’s not-asked reading, named: None → NotAsked, Some → Asked — the mechanical migration step for gated facts built with flag.then(...).

fn from(o: Option<T>) -> Asked<T>

Converts to this type from the input type.

impl<T: PartialEq> PartialEq for Asked<T>

fn eq(&self, other: &Asked<T>) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl<T: Serialize> Serialize for Asked<T>

fn serialize<S: Serializer>(&self, s: S) -> Result<S::Ok, S::Error>

Asked is transparent; NotAsked serializes as null — reached only if a field forgets its skip_serializing_if, in which case it degrades exactly as the Option it replaced would have.

impl<T: PartialEq> StructuralPartialEq for Asked<T>