class Fbe::Award::Bill

def greeting
  items = @lines.map { |l| "#{format('%+d', l[:v])} #{l[:t]}" }
  case items.size
  when 0
    "You've earned nothing. "
  when 1
    "You've earned #{format('%+d', points)} points. "
  else
    "You've earned #{format('%+d', points)} points for this: #{items.join('; ')}. "
  end
end