Struct Phase 

pub struct Phase<S> {
    pub name: &'static str,
    pub forward: ForwardStep<S>,
    pub rollback: RollbackStep<S>,
}

A single phase of the transactional apply pipeline.

The forward step is the work done while applying; if it returns Err, the pipeline aborts and rolls back ALREADY-APPLIED phases in reverse. The rollback closure is invoked only if the forward step previously succeeded.

This is a pure data type — the executor lives in apply_phases_with_rollback and is unit-tested independently of any real subsystem.

Fields

name: &'static str

Human-readable name for log/error messages.

forward: ForwardStep<S>

Apply step. Borrows the shared state mutably.

rollback: RollbackStep<S>

Rollback step. Only invoked if forward succeeded.