Split Controller trait into types and behavior

src/controller.rs

@@ -5,15 +5,19 @@ use std::future::Future;
 
 /// Asynchronous context listener task.
 ///
-/// Listens for changes in [`Controller::Context`] and updates the
-/// corresponding hardware state accordingly, e.g. LEDs, screens,
+/// Listens for changes in [`ControllerTypes::Context`] and updates
+/// the corresponding hardware state accordingly, e.g. LEDs, screens,
 /// or motorized jog wheels and faders.
 pub type BoxedControllerTask = Box<dyn Future<Output = ()> + Send + 'static>;
 
-pub trait Controller {
+pub trait ControllerTypes {
     type Context;
     type InputEvent;
     type ControlAction;
+}
+
+pub trait Controller {
+    type Types: ControllerTypes;
 
     /// Attach a context listener task.
     ///
@@ -24,7 +28,10 @@ pub trait Controller {
     ///
     /// Controllers that don't need a task may return `None`.
     #[must_use]
-    fn attach_context_listener(&mut self, context: &Self::Context) -> Option<BoxedControllerTask>;
+    fn attach_context_listener(
+        &mut self,
+        context: &<Self::Types as ControllerTypes>::Context,
+    ) -> Option<BoxedControllerTask>;
 
     /// Map a generic input event into a control action.
     ///
@@ -35,5 +42,8 @@ pub trait Controller {
     /// is unsupported and should be ignored or if it only affects the internal
     /// state then `None` could be returned.
     #[must_use]
-    fn map_input_event(&mut self, event: Self::InputEvent) -> Option<Self::ControlAction>;
+    fn map_input_event(
+        &mut self,
+        event: <Self::Types as ControllerTypes>::InputEvent,
+    ) -> Option<<Self::Types as ControllerTypes>::ControlAction>;
 }

src/lib.rs

@@ -31,7 +31,7 @@ use std::{
 };
 
 mod controller;
-pub use self::controller::{BoxedControllerTask, Controller};
+pub use self::controller::{BoxedControllerTask, Controller, ControllerTypes};
 
 pub mod devices;