Type alias Tuple4<X1, X2, X3, X4>
Tuple4<X1, X2, X3, X4>: undefined extends X4 ? undefined extends X3 ? undefined extends X2 ? undefined extends X1 ? [X1?, X2?, X3?, X4?] : [X1, X2?, X3?, X4?] : [X1, X2, X3?, X4?] : [X1, X2, X3, X4?] : [X1, X2, X3, X4]