chore: further cleanup

src/core/handle.rs

@@ -45,3 +45,41 @@ pub enum AppEvent {
     /// JACK notification
     Jack(JackEvent)
 }
+
+pub type KeyHandler<T> = &'static dyn Fn(&mut T)->Usually<bool>;
+
+pub type KeyBinding<T> = (
+    KeyCode, KeyModifiers, &'static str, &'static str, KeyHandler<T>
+);
+
+pub type KeyMap<T> = [KeyBinding<T>];
+
+pub fn handle_keymap <T> (
+    state: &mut T, event: &AppEvent, keymap: &KeyMap<T>,
+) -> Usually<bool> {
+    match event {
+        AppEvent::Input(Event::Key(event)) => {
+            for (code, modifiers, _, _, command) in keymap.iter() {
+                if *code == event.code && modifiers.bits() == event.modifiers.bits() {
+                    return command(state)
+                }
+            }
+        },
+        _ => {}
+    };
+    Ok(false)
+}
+
+#[macro_export] macro_rules! key {
+    ($k:ident $(($char:literal))?, $m:ident, $n: literal, $d: literal, $f: expr) => {
+        (KeyCode::$k $(($char))?, KeyModifiers::$m, $n, $d, &$f)
+    };
+}
+
+#[macro_export] macro_rules! keymap {
+    ($T:ty { $([$k:ident $(($char:literal))?, $m:ident, $n: literal, $d: literal, $f: expr]),* $(,)? }) => {
+        &[
+            $((KeyCode::$k $(($char))?, KeyModifiers::$m, $n, $d, &$f as KeyHandler<$T>)),*
+        ] as &'static [KeyBinding<$T>]
+    }
+}