Function dbus::arg::cast_mut

pub fn cast_mut<'a, T: 'static>(
    a: &'a mut (dyn RefArg + 'static)
) -> Option<&'a mut T>

Cast a RefArg as a specific type (shortcut for any_mut + downcast_mut)

Panic

Will panic if the interior cannot be made mutable, e g, if encapsulated inside a Rc with a reference count > 1.