macro_rules! trigger {
(KeyBinding, $key:literal, $location:expr) => { ... };
(KeyBinding, $key:literal,) => { ... };
(KeyBinding, $key:ident, $location:expr) => { ... };
(KeyBinding, $key:ident,) => { ... };
(MouseBinding, $base:ident::$button:ident,) => { ... };
}