static fillWithin(a, fromIndex, toIndex, val) {
			Arrays.rangeCheck(a.length, fromIndex, toIndex);
			for (let i = fromIndex; i < toIndex; i++)
				a[i] = val;
		}
Assigns the specified int value to each element of the specified
range of the specified array of ints.  The range to be filled
extends from index {@code fromIndex}, inclusive, to index
{@code toIndex}, exclusive.  (If {@code fromIndex==toIndex}, the
range to be filled is empty.)

@param a the array to be filled
@param fromIndex the index of the first element (inclusive) to be
       filled with the specified value
@param toIndex the index of the last element (exclusive) to be
       filled with the specified value
@param val the value to be stored in all elements of the array
@throws IllegalArgumentException if {@code fromIndex > toIndex}
@throws ArrayIndexOutOfBoundsException if {@code fromIndex < 0} or
        {@code toIndex > a.length}