🚏 Stopping Point

No Interruptibility

fn execute(
    params: Params,
) -> Outcome {
    let output_1 = step_1(params);
    let output_2 = step_2(output_1);
    let outcome = step_3(output_2);

    return outcome;
}

Basic

fn execute(
    interrupt_rx: mut Receiver<InterruptSignal>,
    params: Params,
) -> ControlFlow<InterruptSignal, Outcome> {
    let () = interruptibility_check(&mut interrupt_rx)?;
    let output_1 = step_1(params);

    let () = interruptibility_check(&mut interrupt_rx)?;
    let output_2 = step_2(output_1);

    let () = interruptibility_check(&mut interrupt_rx)?;
    let outcome = step_3(output_2);

    ControlFlow::Continue(outcome)
}

fn interruptibility_check(receiver: &mut Receiver<InterruptSignal>)
-> ControlFlow<InterruptSignal, ()> {
    if let Ok(interrupt_signal) = interrupt_rx.try_recv() {
        ControlFlow::Continue(())
    } else {
        ControlFlow::Break(interrupt_signal)
    }
}

Fine Grained Interruptibility

fn execute(
    interrupt_rx: mut Receiver<InterruptSignal>,
    params: Params,
) -> ControlFlow<InterruptSignal, Outcome> {
    let () = interruptibility_check(&mut interrupt_rx)?;
    let output_1 = step_1(&mut interrupt_rx, params);

    // ..
}

fn step_1(
    interrupt_rx: mut Receiver<InterruptSignal>,
    params: Params,
) -> ControlFlow<Output1, Outcome> {
    let mut output_1 = Output1::new();
    for i in 0..1_000_000 {
        if i % 1_000 == 0 {
            let () = interruptibility_check(&mut interrupt_rx)?;
        }
        do_something(output_1, params, i);
    }

    ControlFlow::Continue(output_1)
}