use core::future::Future; pub trait Delay { type DelayFuture<'a>: Future + 'a where Self: 'a; /// Future that completes after now + millis fn delay_ms(&mut self, millis: u64) -> Self::DelayFuture<'_>; /// Future that completes after now + micros fn delay_us(&mut self, micros: u64) -> Self::DelayFuture<'_>; }