如何检测 BasicObject 代理？

Question

我正在使用 BasicObject 代理，我需要检测我是否传递了实际对象或此类代理。问题是 is_a? 或 class 等方法未定义

module ControllerProxyable
  extend ActiveSupport::Concern

  included do
    attr_reader :controller
    delegate :current_user, to: :controller
  end

  def controller_proxy(controller)
    # is_a? actually is NOT defined for a BasicObject causes the following to crash
    @controller = if controller.is_a?(ControllerProxy) 
      controller
    else
      ControllerProxy.new(controller)
    end
  end
end

class ControllerProxy < BasicObject
  def initialize(controller = nil)
    @controller = controller
  end

  def some_proxy_method
  end

  # def respond_to and respond_to_missing not relevant here
end

这是我如何使用它的示例：

class Foo
  include ControllerProxyable

  def initialize(controller: nil)
    controller_proxy(controller)
  end

  def bar
    bar ||= Bar.new(controller: controller)
  end
end

class Bar
  include ControllerProxyable

  def initialize(controller: nil)
    controller_proxy(controller)
  end
end

因此以下内容不起作用

Foo.new(controller: nil).bar.some_proxy_method

如何为代理定义 is_a?（或实际识别我正在使用代理）？

Answer 1

我实际上找到了 RUby 2 here 的答案。我的问题几乎感觉像是重复的，但就我而言，我说的是 basicObject class 的扩展，而不是修补 BasicObject class 本身

对于这样的用例，这变成：

def controller_proxy(controller)
    # Note that is_a? is not defined for a proxy
    @controller = if Kernel.instance_method(:class).bind(controller).call <= ServiceControllerProxy
      controller
    else
      ServiceControllerProxy.new(controller)
    end
  end

Answer 2

Problem is that methods such as is_a? or class are not defined

解决问题"some method is not defined"的明显方法是定义方法：

class ControllerProxy
  def class; ControllerProxy end

  def is_a?(mod)
    self.class < mod
  end
end

但是！这违背了代理的全部目的，即与真实事物无法区分。更好的方法是 IMO:

class ControllerProxy
  def class; Controller end

  def is_a?(mod)
    Controller < mod
  end
end

如何检测 BasicObject 代理？

How to detect a BasicObject Proxy?

ruby

proxy

ruby-2.3