My Magic Authenticator implementation framework reference skeleton

MagicAuthenticator.rb

class FBAuthenticator
  def initialize(uid, token)
    @uid = uid
    @token = token
  end

  def authenticate(args)
    raise ArgumentError unless args.has_key?(:success)
    raise ArgumentError unless args.has_key?(:fail)

    authenticated = magic_authentication
    if Success === authenticated
      args[:success].new(@uid, @token).handle
    else
      args[:fail].new(authenticated.to_s).handle
    end
  end

  def magic_authentication
    outer_block do |outer_response|
      inner_block do |inner_response|
        if outer_response && inner_response
          return Success.new
        else
          return Error.new("VERY WOW, MUCH ERROR")
        end
      end
    end
  end

  def outer_block
    yield false
  end

  def inner_block
    yield true
  end

  class Success

  end

  class Error
    def initialize(msg)
      @message = msg
    end

    def to_s
      @message
    end
  end
end

class AuthenticatedHandler
  def initialize(uid, token)
    @uid, @token = uid, token
  end

  def handle
    puts "AUTHENTICATED WITH #{@uid}/#{@token}"
  end
end

class NotAuthenticatedHandler
  def initialize(err)
    @error = err
  end

  def handle
    puts "BIG FAT NONO: #{@error}"
  end
end


FBAuthenticator.new(123, 456).authenticate(
  success: AuthenticatedHandler,
  fail:    NotAuthenticatedHandler)