Struct EngineHandle 

pub struct EngineHandle<E> { /* private fields */ }

A running engine, reachable from outside its drive.

Cheap to clone: both halves are channel senders. Cloning does not keep the engine alive — the drive ends when its policy says so, and every handle then reports EngineGone.

Implementations

impl<E> EngineHandle<E>

pub const fn new(inbox: Sender<Msg>, events: Sender<E>) -> Self

Wrap an existing pair. The daemon supplies its own event bus, because it has to subscribe before the run starts to catch the line that names the session.

pub fn with_capacity(inbox: Sender<Msg>, capacity: usize) -> Self

where E: Clone,

Wrap an inbox with a fresh event bus of capacity.

pub async fn send(&self, msg: Msg) -> Result<(), EngineGone>

Deliver a message to the running engine.

Awaits a slot when the inbox is full: that is backpressure from a run that is behind on its own effects, and dropping the message instead would lose a user’s prompt. Use EngineHandle::try_send where the caller cannot wait.

Errors

EngineGone once the drive has ended.

pub fn try_send(&self, msg: Msg) -> Result<(), EngineGone>

Deliver without waiting. Reports EngineGone for a finished engine and, for a full inbox, hands the message back the same way — a caller that cannot wait cannot queue either.

Errors

EngineGone when the drive has ended or its inbox is full.

pub fn subscribe(&self) -> Receiver<E>

Watch what the engine’s observer publishes, from now on.

A subscriber that needs what it missed reads the session event log first and then joins here — the shape subscribe_task already uses, and the reason this is a broadcast and not a replayable stream.

pub const fn publisher(&self) -> &Sender<E>

The publishing end, for whatever observer feeds this handle.

pub fn is_running(&self) -> bool

Whether the drive is still pumping. Racy by nature — a run can end between the check and the send, which is why EngineHandle::send reports it too.

Trait Implementations

impl<E> Clone for EngineHandle<E>

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<E> Debug for EngineHandle<E>

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

Formats the value using the given formatter.