mperham

class TaxCode
  GENERATORS = {
    :us => lambda { |id| "US-#{id}" },
    :br => lambda { |id| "#{id + 9}-BRA" },
  }

  def self.generate(code, id)
    gen = GENERATORS[code] || raise ArgumentError, "No generator for country #{code}"
    gen.call(id)
  end