Enum RetentionReason 

#[non_exhaustive]
pub enum RetentionReason {
    RemovalWouldAlterPayload,
    StructurallyRequired,
    DerivedFromPayload,
}

Why a handler kept something it could see.

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.

RemovalWouldAlterPayload

Removing it would have altered the payload — re-encoding pixels, for instance — which PRD §8.1 forbids. Preserving the payload wins, and the limitation gets documented.

StructurallyRequired

The format requires it to be present for the file to remain valid.

DerivedFromPayload

It is computed from the payload the file still carries, so removing it would hide nothing from anyone holding that file. FLAC’s MD5 of the unencoded audio is the case this exists for: a fingerprint, and one the holder can recompute (ADR-0038). Declared rather than removed — and declared rather than passed over, because it does link one copy of a recording to another.

Trait Implementations

impl Clone for RetentionReason

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for RetentionReason

impl Debug for RetentionReason

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

Formats the value using the given formatter.

impl Eq for RetentionReason

impl PartialEq for RetentionReason

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for RetentionReason