Module C2 - Async foundations

Slides

C2.1

We're going to build an observable variable, a bit similar in idea to a condvar.

It should have the following use:

#![allow(unused)]
fn main() {
pub static CPU_TEMPERATURE: Observable<f32> = Observable::new(20.0);

async fn throttle_if_cpu_temp_high(cpu: &mut Cpu) -> ! {
    loop {
        CPU_TEMPERATURE
            .wait_until(|temperature| temperature > 90.0)
            .await;

        cpu.throttle();

        CPU_TEMPERATURE
            .wait_until(|temperature| temperature < 80.0)
            .await;

        cpu.un_throttle();
    }
}
}

Go to exercise C2/1-observable and implement the type. Run cargo test in that folder to check if your implementation works.

Extra questions and challenges:

• For the embedded devs, make the library no_std
• Can we get rid of the Clone bound? If not, why not? If we can, what would the API look like?
• Async API design is hard. The Observable API has its limitations too. What are they? Can it be improved?
• Make the Observable support multiple wakers. (For no_std this is extra challenging)