Enum Step 

pub enum Step<T> {
    Event(T),
    CaughtUp,
}

One item of a phase-aware subscription cursor: a decoded event, or the caught-up boundary marker emitted once when replay finishes and the cursor switches to live tailing.

Everything yielded before CaughtUp is replay (catch-up over the backlog); everything after is live. T is the item payload — Decoded<E> per-stream, (AllPosition, StreamKey, Decoded<E>) for $all.

Exhaustive (no #[non_exhaustive], per project rule): the two variants are frozen at 1.0. A lag signal (FellBehind) is intentionally omitted — the live loop does not distinguish a lagging live consumer from a caught-up one, and a consumer can observe lag from positions.

Variants

Event(T)

A delivered event (replay or live — the phase is told by the preceding CaughtUp).

CaughtUp

The backlog is drained; subsequent items are live. Emitted exactly once.

Implementations

impl<T> Step<T>

pub fn event(self) -> Option<T>

The event payload, or None for CaughtUp.

pub const fn is_caught_up(&self) -> bool

true iff this is the CaughtUp marker.

pub fn map<U>(self, f: impl FnOnce(T) -> U) -> Step<U>

Map the carried payload, leaving CaughtUp untouched. The phase marker flows through every transform (drop-the-tag in subscribe, decode in .decoded()) so a boundary is never lost.

Trait Implementations

impl<T: Clone> Clone for Step<T>

fn clone(&self) -> Step<T>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<T: Copy> Copy for Step<T>

impl<T: Debug> Debug for Step<T>

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

Formats the value using the given formatter.

impl<T: Eq> Eq for Step<T>

impl<T: PartialEq> PartialEq for Step<T>

fn eq(&self, other: &Step<T>) -> bool

Equality operator ==.

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

Inequality operator !=.

impl<T: PartialEq> StructuralPartialEq for Step<T>