Crate events 

Async manual-reset and auto-reset event primitives.

This crate provides async event primitives:

• Manual-reset events (ManualResetEvent, LocalManualResetEvent) — a gate that, once set, releases all current and future awaiters until explicitly reset via reset().
• Auto-reset events (AutoResetEvent, LocalAutoResetEvent) — a signal that releases at most one awaiter per set() call, automatically consuming the signal when an awaiter is released.

Each family comes in a thread-safe variant (Send + Sync) and a single-threaded Local variant for improved efficiency when thread safety is not required.

Boxed vs embedded storage

Every event type can be created in two ways:

• boxed() — the event manages its own storage. Simple to use: the returned handle is Clone and can be shared freely. Best for most use cases.
• embedded() — borrows caller-provided storage (Embedded* types) instead of allocating. This eliminates one allocation per event, which matters when events are created on a hot path or embedded inside other data structures. The caller must ensure the storage outlives all handles and wait futures, and the embedded() call is unsafe to reflect this contract.

Events are lightweight cloneable handles. All clones from the same boxed() or embedded() origin share the same underlying state.

Manual-reset example

use events::ManualResetEvent;

#[tokio::main]
async fn main() {
    let event = ManualResetEvent::boxed();
    let setter = event.clone();

    // Producer opens the gate from a background task.
    tokio::spawn(async move {
        setter.set();
    });

    // Consumer waits for the gate to open.
    event.wait().await;

    // The gate stays open — it must be explicitly closed.
    assert!(event.try_wait());
}

Auto-reset example

use events::AutoResetEvent;

#[tokio::main]
async fn main() {
    let event = AutoResetEvent::boxed();
    let setter = event.clone();

    // Producer signals from a background task.
    tokio::spawn(async move {
        setter.set();
    });

    // Consumer waits for the signal.
    event.wait().await;

    // Signal was consumed.
    assert!(!event.try_wait());
}

Modules

futures

Future types returned by event wait() methods.

Structs

AutoResetEvent

Thread-safe async auto-reset event.

EmbeddedAutoResetEvent

Embedded-state container for AutoResetEvent.

EmbeddedAutoResetEventRef

Handle to an embedded AutoResetEvent.

EmbeddedLocalAutoResetEvent

Embedded-state container for LocalAutoResetEvent.

EmbeddedLocalAutoResetEventRef

Handle to an embedded LocalAutoResetEvent.

EmbeddedLocalManualResetEvent

Embedded-state container for LocalManualResetEvent.

EmbeddedLocalManualResetEventRef

Handle to an embedded LocalManualResetEvent.

EmbeddedManualResetEvent

Embedded-state container for ManualResetEvent.

EmbeddedManualResetEventRef

Handle to an embedded ManualResetEvent.

LocalAutoResetEvent

Single-threaded async auto-reset event.

LocalManualResetEvent

Single-threaded async manual-reset event.

ManualResetEvent

Thread-safe async manual-reset event.