Enum HistoricalSupport 

pub enum HistoricalSupport {
    Content,
    MetadataOnly,
    Unsupported,
}

What History can do with one resource type.

Variants

Content

Every version can be shown, compared and restored by content: the type declared a restore schema.

MetadataOnly

The type reads its record but declares no restore schema: a version reads through the type’s own adapter and lists with its metadata, and a restore brings what it held back byte for byte.

Unsupported

The type declares no content it could restore or show: its versions are named by address only.

Implementations

impl HistoricalSupport

pub fn of( scope: &HistoryScopeDefinition, reads_content: bool, ) -> HistoricalSupport

What the scope’s own declaration says its resource type supports; reads_content says the type declared a read adapter (ResourceSpec::READABLE).

pub fn declares_schema(self) -> bool

Whether the scope’s declaration carries a restore schema: a Some even when that schema cannot name what replaces what.

pub fn restorable(self) -> bool

Whether a version of this type can be restored at all.

Trait Implementations

impl Clone for HistoricalSupport

fn clone(&self) -> HistoricalSupport

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for HistoricalSupport

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

Formats the value using the given formatter.

impl Hash for HistoricalSupport

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

where __H: Hasher,

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 PartialEq for HistoricalSupport

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

impl Eq for HistoricalSupport

impl StructuralPartialEq for HistoricalSupport