class Tins::StringVersion::Version

def []=(index, value)
  value = value.to_i
  value >= 0 or raise ArgumentError, "version numbers can't contain negative numbers like #{value}"
  a = array
  @array = nil
  a[index] = value
  a.map! { |x| x.nil? ? 0 : x }
  @version.replace a * '.'
end