redef fun search_all_in(b) do
		var ret = new Array[Int]
		var pos = 0
		loop
			pos = first_index_in_from(b, pos)
			if pos == -1 then return ret
			ret.add pos
			pos += 1
		end
	end

	redef fun search_all_in(b) do
		var ret = new Array[Int]
		var pos = first_index_in_from(b, 0)
		if pos == -1 then return ret
		pos = pos + 1
		ret.add pos
		loop
			pos = first_index_in_from(b, pos)
			if pos == -1 then return ret
			ret.add pos
			pos += length
		end
	end