Struct Absent 

pub struct Absent;

Type for a value that must be absent.

This should be accompanied by serde attributes to indicate that:

• the default value should be taken #[serde(default)]
• it should never be serialized #[serde(skip_serializing)] (or #[serde(skip_serializing_if = "::json_serde::always")]; see always)

Deserialization always fails–the field must not be present–and serialization fails if it is ever invoked, hence the attributes above. With the schemars08 and schemars1 features, Absent’s JsonSchema implementation is the false schema, which no value satisfies.

Trait Implementations

impl Clone for Absent

fn clone(&self) -> Absent

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for Absent

impl Debug for Absent

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

Formats the value using the given formatter.

impl Default for Absent

fn default() -> Absent

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Absent

fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>

where D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for Absent

impl Hash for Absent

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl JsonSchema for Absent

Available on crate feature schemars08 only.

fn schema_name() -> String

The name of the generated JSON Schema.

fn json_schema(_: &mut SchemaGenerator) -> Schema

Generates a JSON Schema for this type.

fn is_referenceable() -> bool

Whether JSON Schemas generated for this type should be re-used where possible using the $ref keyword.

fn schema_id() -> Cow<'static, str>

Returns a string that uniquely identifies the schema produced by this type.

impl JsonSchema for Absent

Available on crate feature schemars1 only.

fn schema_name() -> Cow<'static, str>

The name of the generated JSON Schema.

fn json_schema(_: &mut SchemaGenerator) -> Schema

Generates a JSON Schema for this type.

fn inline_schema() -> bool

Whether JSON Schemas generated for this type should be included directly in parent schemas, rather than being re-used where possible using the $ref keyword.

fn schema_id() -> Cow<'static, str>

Returns a string that uniquely identifies the schema produced by this type.

impl Ord for Absent

fn cmp(&self, other: &Absent) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for Absent

fn eq(&self, other: &Absent) -> bool

Equality operator ==.

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

Inequality operator !=.

impl PartialOrd for Absent

fn partial_cmp(&self, other: &Absent) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

Tests less than (for self and other) and is used by the < operator.

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

Tests less than or equal to (for self and other) and is used by the <= operator.

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

Tests greater than (for self and other) and is used by the > operator.

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

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Serialize for Absent

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

where S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for Absent