Function caseWhen

caseWhen<N extends number, R extends Any<unknown, N>>(
    ...cases: [WhenThen<R>, ...WhenThen<R>[]],
): AsNullable<R>

caseWhen<N extends number, T extends Any<unknown, N>>(
    ...casesAndElse: [WhenThen<T>, ...WhenThen<T>[], T],
): T

caseWhen<N extends number, T extends Any<unknown, N>>(
    ...casesAndElse: [
        WhenThen<AsNullable<T>>,
        ...WhenThen<AsNullable<T>>[],
        T,
    ],
): AsNullable<T>