Enum FieldPresence 

#[non_exhaustive]
pub enum FieldPresence {
    Explicit,
    Implicit,
    LegacyRequired,
}

Controls whether field presence is tracked.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Explicit

Presence is tracked explicitly (has-bit or Option).

Implicit

No presence tracking; default value means “not set.”

LegacyRequired

Legacy required behavior from proto2.

Trait Implementations

impl Clone for FieldPresence

fn clone(&self) -> FieldPresence

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for FieldPresence

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

Formats the value using the given formatter.

impl PartialEq for FieldPresence

fn eq(&self, other: &FieldPresence) -> 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 Copy for FieldPresence

impl Eq for FieldPresence

impl StructuralPartialEq for FieldPresence