Enum LabelPolicy 

pub enum LabelPolicy {
    Opaque,
    EntityNameDefault,
    ExternalKeyDefault,
    OpaqueByDefault,
}

Controls how IDs are displayed to humans (via .labeled()).

Scope

This enum affects only human-facing output. It does NOT affect:

• Display/to_string() → always canonical
• Serialize/serde → always canonical
• Database storage → always canonical
• ID construction → no complexity added
• Equality/hashing → based on canonical ID only

Usage

Specified on the Label trait (and delegated from Provenance) as POLICY constant. Controls the default behavior of .labeled() when called with no arguments.

Variants

Opaque

No preference; defaults to canonical output but encourages explicit mode selection.

Used when the provenance doesn’t have a strong default preference.

Output Scenarios:

• id.to_string(): "value" (Canonical)
• id.labeled().to_string(): "value" (Default = None)
• id.labeled().mode(LabelMode::None).to_string(): "value"
• id.labeled().mode(LabelMode::Short).to_string(): "Entity::value"
• id.labeled().mode(LabelMode::Full).to_string(): "Entity@prov::value"

EntityNameDefault

Default to showing the entity type name in human output.

Used for internal origins (Generated, Derived) where the entity type provides sufficient context without needing to show provenance details.

Output Scenarios:

• id.to_string(): "value" (Canonical)
• id.labeled().to_string(): "Entity::value" (Default = Short)
• id.labeled().mode(LabelMode::None).to_string(): "value"
• id.labeled().mode(LabelMode::Short).to_string(): "Entity::value"
• id.labeled().mode(LabelMode::Full).to_string(): "Entity@prov::value"

ExternalKeyDefault

Default to showing both entity and provenance in human output.

Used for external origins (External, Imported) where knowing the source system is critical for understanding and identifying the ID.

Output Scenarios:

• id.to_string(): "value" (Canonical)
• id.labeled().to_string(): "Entity@prov::value" (Default = Full)
• id.labeled().mode(LabelMode::None).to_string(): "value"
• id.labeled().mode(LabelMode::Short).to_string(): "Entity::value"
• id.labeled().mode(LabelMode::Full).to_string(): "Entity@prov::value"

OpaqueByDefault

Hide all labels by default; only show on explicit request.

Used for sensitive or transient sources (Temporary, ClientProvided) where the ID itself might be sensitive and context shouldn’t leak in logs unless necessary.

Output Scenarios:

• id.to_string(): "value" (Canonical)
• id.labeled().to_string(): "value" (Default = None)
• id.labeled().mode(LabelMode::None).to_string(): "value"
• id.labeled().mode(LabelMode::Short).to_string(): "Entity::value"
• id.labeled().mode(LabelMode::Full).to_string(): "Entity@prov::value"

Trait Implementations

impl Clone for LabelPolicy

fn clone(&self) -> LabelPolicy

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for LabelPolicy

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

Formats the value using the given formatter.

impl From<LabelPolicy> for LabelMode

fn from(policy: LabelPolicy) -> Self

Converts to this type from the input type.

impl PartialEq for LabelPolicy

fn eq(&self, other: &LabelPolicy) -> 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 LabelPolicy

impl Eq for LabelPolicy

impl StructuralPartialEq for LabelPolicy