class Object
  def metaclass; class << self; self; end; end
  def meta_eval &blk; metaclass.instance_eval &blk; end
  def meta_def name, &blk
    meta_eval { define_method name, &blk }
  end
  def class_def name, &blk
    class_eval { define_method name, &blk }
  end
end

class ProoflinkError < StandardError
  def self.message(msg)
    meta_def :default_message do; msg; end
  end

  def self.status(status)
    meta_def :default_status do; status; end
  end

  def self.code(code)
    meta_def :default_code do; code; end
  end

  message "default"
  status 100
  code :default_error

  attr_accessor :message, :status, :code

  def initialize(msg=nil, status=nil, code=nil)
    super(msg || self.class.default_message)
    @message = msg || self.class.default_message
    @status = status || self.class.default_status
    @code = code || self.class.default_code
  end
end

class TestError < ProoflinkError
  message "test error"
  status 999
  code :test_error
end

begin
  raise ProoflinkError
rescue Exception => e
  puts e.inspect
  puts e.message
  puts e.status
  puts e.code
end
begin
  raise TestError
rescue Exception => e
  puts e.inspect
  puts e.message
  puts e.status
  puts e.code
end