_TupleOf

type _TupleOf<
    L extends number,
    Fill,
    Accumulator extends UnknownArray
> = number extends L
    ? Fill[]
    : L extends Accumulator["length"]
      ? Accumulator
      : _TupleOf<L, Fill, [...Accumulator, Fill]>;

type _TupleOf<
    L extends number,
    Fill,
    Accumulator extends UnknownArray
> = number extends L
    ? Fill[]
    : L extends Accumulator["length"]
      ? Accumulator
      : _TupleOf<L, Fill, [...Accumulator, Fill]>;