Enum LogVersion 

pub enum LogVersion {
    Current,
    Older,
    Ahead,
    NotAVersion,
}

Where a ledger line’s v stands against the version this build writes. The one authority for “which ledgers open”; every reader that compares a v asks readable_log_v rather than comparing again.

Exhaustive on purpose: a reader that handles three of these and defaults the fourth is how an unversioned line came to be reported as a broken chain.

Variants

Current

Exactly what this build writes. Readable, and appendable.

Older

Written by an older build, at or above the first version. Readable: the ledger is append-only and its history stays on disk, so every version from 1 upwards still parses.

Ahead

Written by a newer build. Refused whole rather than read in part: a line this build does not fully understand must not become the prefix of a chain it then extends.

NotAVersion

Below the first version anybody ever wrote, 0 included. No build produced this, so it is a damaged or foreign line rather than an old one.

Trait Implementations

impl Clone for LogVersion

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 LogVersion

impl Debug for LogVersion

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

Formats the value using the given formatter.

impl Eq for LogVersion

impl PartialEq for LogVersion

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for LogVersion