pandet

A lightweight library that helps you detect failure of spawned async tasks without having to .await their handles. Useful when you are spawning lots of detached tasks but want to fast-fail if a panic occurs.

```rust use pandet::{PanicAlert, OnPanic};

let (alert, detector) = PanicAlert::new();

// Whichever async task spawner task::spawn( async move { panic!(); } .on_panic(&detector()) // 👈 Binds the alert's detector );

drop(detector); assert!(alert.await.is_some()); ```

For !Send tasks, there is the UnsendOnPanic trait: ```rust use pandet::{PanicAlert, UnsendOnPanic};

let (alert, detector) = PanicAlert::new();

task::spawnlocal( async move { panic!(); } .unsendon_panic(&detector) );

assert!(alert.await.is_some()); ```

Refined control over how to handle panics can also be implemented with PanicMonitor which works like a stream of alerts. You may also pass some information to the alert/monitor when a panic occurs: ```rust use futures::StreamExt; use pandet::{PanicMonitor, OnPanic};

// Any Unpin + Send + 'static type works struct PanicInfo { task_id: usize, }

let (mut monitor, detector) = PanicMonitor::::new(); // Or simply PanicMonitor::new() for taskid in 0..=10 { let detector = detector.clone(); task::spawn( async move { if taskid % 3 == 0 { panic!(); } } // Informs the monitor of which task panicked .onpanicinfo(&detector, PanicInfo { task_id }) ); }

drop(detector); let cnt = 0; while let Some(res) = monitor.next().await { cnt += 1; let info = res.0; asserteq!(info.taskid % 3, 0); } assert_eq!(cnt, 4); ```