Enum LossCause 

pub enum LossCause {
    Write(WriteId),
    Rules(BTreeSet<Rule>),
    Excluded {
        write: WriteId,
        version: u32,
    },
    Dependency {
        write: WriteId,
        sources: Vec<ChangeId>,
    },
    NotAuthorized {
        write: WriteId,
        reason: AuthorizationFailure,
    },
}

The replacing write, removal rules, or boundary that excluded a write.

Variants

Write(WriteId)

A replacing write that had not read the lost setter.

Rules(BTreeSet<Rule>)

Every rule holding when the row was removed.

Excluded

A breaking schema change that excluded the write, or whose migration write deleted a hidden row. Resets create no losses (§19.4).

Fields

write: WriteId

The excluded write, including deletions with no retained cells.

version: u32

The schema version reached by the breaking change.

Dependency

An admitted row change that used data which does not survive (§9.5): its generation source, a cell setter it replaced, a source its operations used, or a foreign-key cause in its own write.

Fields

write: WriteId

The write whose row change this is, even for an empty delete.

sources: Vec<ChangeId>

Failed sources in role order, with repeats: generation, replaced setters, additional execution sources, then foreign-key causes.

NotAuthorized

A member’s row change without permission: a direct change of another member’s owned row, or a foreign-key effect the receiver could not derive exactly from an authorized direct change (§9.6).

Fields

write: WriteId

The write whose row change this is, even for an empty delete.

reason: AuthorizationFailure

Why the change was refused.

Implementations

impl LossCause

pub fn change_write(&self) -> Option<WriteId>

The original change’s own write, for a frozen change loss.

pub fn freezes_change(&self) -> bool

A frozen original row change: excluded, dependent or unauthorized.

Trait Implementations

impl Clone for LossCause

fn clone(&self) -> LossCause

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for LossCause

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

Formats the value using the given formatter.

impl PartialEq for LossCause

fn eq(&self, other: &LossCause) -> 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 Eq for LossCause

impl StructuralPartialEq for LossCause