Enum MetadataPolicy 

pub enum MetadataPolicy {
    Optional,
    Required,
    Ignore,
    Persistent,
}

Variants

Optional

Apply when set, clear when not

Required

Error if not set

Ignore

Never apply the set metadata

Persistent

Keep the prior metadata if not set

Trait Implementations

impl Clone for MetadataPolicy

fn clone(&self) -> MetadataPolicy

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for MetadataPolicy

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

Formats the value using the given formatter.

impl Default for MetadataPolicy

fn default() -> MetadataPolicy

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for MetadataPolicy

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for MetadataPolicy

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for MetadataPolicy

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl ValueEnum for MetadataPolicy

fn value_variants<'a>() -> &'a [Self]

All possible argument values, in display order.

fn to_possible_value<'a>(&self) -> Option<PossibleValue>

The canonical argument value.

fn from_str(input: &str, ignore_case: bool) -> Result<Self, String>

Parse an argument into Self.

impl Copy for MetadataPolicy

impl Eq for MetadataPolicy

impl StructuralPartialEq for MetadataPolicy