Use unified mrb_args_req_and_opt instead of bitwise or
@@ -19,7 +19,7 @@ pub fn init(interp: &mut Artichoke) -> InitializeResult<()> {
.value_is_rust_object()
// Constructor
.add_self_method("now", time_self_now, sys::mrb_args_none())?
- .add_self_method("at", time_self_at, sys::mrb_args_req(1) | sys::mrb_args_opt(3))?
+ .add_self_method("at", time_self_at, sys::mrb_args_req_and_opt(1, 3))?
.add_self_method("utc", time_self_mkutc, sys::mrb_args_any())?
.add_self_method("gm", time_self_mkutc, sys::mrb_args_any())?
.add_self_method("local", time_self_mktime, sys::mrb_args_any())?
