pub type Event_PadAxis_Callback = Option<unsafe extern "C" fn(obj: *mut c_void, port: c_int, axis: c_int, x: f32, y: f32)>;
enum Event_PadAxis_Callback { None, Some(unsafe extern "C" fn(*mut c_void, i32, i32, f32, f32)), }
No value.
Some value of type T.
T