class Covered::Coverage

def mark(line_number, value = 1)
	# As currently implemented, @counts is base-zero rather than base-one.
	# Line numbers generally start at line 1, so the first line, line 1, is at index 1. This means that index[0] is usually nil.
	Array(value).each_with_index do |value, index|
		offset = line_number + index
		if @counts[offset]
			@counts[offset] += value
		else
			@counts[offset] = value
		end
	end
end