Hey ya'll, got a new library that's all about waiting for stuff, check it out:
https://crates.io/crates/situwaition
Here's the current version's tokio example (async-std is also supported):
use std::{
result::Result,
sync::{Arc, Mutex},
time::Duration,
};
use situwaition::{runtime::tokio::wait_for, runtime::AsyncWaiter, AsyncSituwaition};
use thiserror::Error;
#[derive(Debug, Error)]
enum ExampleError {
#[error("not done counting yet")]
NotDoneCountingError,
#[error("mutex encounted a poison error")]
MutexPoisonError,
}
// This example uses wait_for to wait for a value that changes, completely synchronously.
//
// By default, wait_for checks every 250ms, and times out after 3 seconds.
// this means the code below should wait 750ms in total, and value should never be above 3.
#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
let value = Arc::new(Mutex::new(0));
let shared_value = value.clone();
eprintln!("finished setup");
let result = wait_for(|| async {
// Get the current value from the mutex
let mut current_value = shared_value
.lock()
.map_err(|_| ExampleError::MutexPoisonError)?;
// Act on the current value
eprintln!("acting on unlocked value... {current_value}");
if *current_value >= 2 {
Ok(42)
} else {
*current_value += 1;
Err(ExampleError::NotDoneCountingError)
}
})
.await?;
assert!(matches!(result, 42));
eprintln!("resulting value is: {}", result);
// This async waiter always fails, so it will resolve to a failure in 500ms
let _ = AsyncWaiter::with_timeout(
|| async { Err(ExampleError::NotDoneCountingError) as Result<(), ExampleError> },
Duration::from_millis(500),
)?
.exec()
.await;
eprintln!("asynchronous always-failing result: {:?}", result);
Ok(())
}
The example is a little contrived but I hope it illustrates how to use the library!
