# Remove an attribute from the list.
	#
	# Parameters:
	#
	# * `index`: index of the attribute (zero-based).
	fun remove_at(index: Int) do
		assert index_in_bounds: index >= 0 and index < length
		index = index * 5
		for i in [1..5] do
			data.remove_at(index)
		end
		length -= 1
	end