pennant 0.5.0

Reusable LED animation effects for embedded projects
Documentation 
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use rgb::RGB8;

/// Async counterpart of [`StatusLed`](crate::StatusLed) for drivers with async I/O.
///
/// This trait mirrors `StatusLed` but uses `async fn` in trait position
/// (stable since Rust 1.75), allowing implementations to yield to an executor
/// during hardware operations (e.g., RMT transmission). The workspace MSRV
/// (see project README) is well past this stabilisation point.
///
/// # Object safety
///
/// This trait is **not** object-safe — `dyn AsyncStatusLed` will not compile.
/// Each implementation produces a distinct future type that cannot be erased
/// through a vtable. Use generics or enum dispatch instead.
///
/// # Example
///
/// ```ignore
/// use pennant::AsyncStatusLed;
/// use rgb::RGB8;
///
/// async fn set_status<L: AsyncStatusLed>(led: &mut L) -> Result<(), L::Error> {
///     led.set_color(RGB8::new(0, 255, 0)).await?;
///     Ok(())
/// }
/// ```
#[allow(async_fn_in_trait)]
pub trait AsyncStatusLed {
    /// The error type returned by async LED operations.
    type Error;

    /// Sets the LED to the specified color, yielding during hardware I/O.
    async fn set_color(&mut self, color: RGB8) -> Result<(), Self::Error>;
}