Ruby on rails 调用基于超级的被调用方值

方法

super

基于

\uuuuu方法\uuuu

调用父方法。 如何基于被调用方调用父方法

class SomeLogic
  DICTIONARY = {
    new_method_1: 'dictionary value 1',
    new_method_2: 'dictionary value 2'
  }

  def initialize(method_name)
    @method_name = method_name
  end

  def call
    DICTIONARY[@method_name]
  end

end

module M

  extend ActiveSupport::Concern

  def base_method
    logic = SomeLogic.new(__callee__).call

    if logic
      logic
    elsif defined?(__callee__)
      super # here analogue of super needed
    else
      {}
    end
  end

  alias_method :new_method_1, :base_method
  alias_method :new_method_2, :base_method
  alias_method :new_method_3, :base_method
end


class A

  prepend M

  def new_method_3
    'foo'
  end

end

预期成果：

A.new.new_method_1 # dictionary value 1
A.new.new_method_2 # dictionary value 2
A.new.new_method_3 # foo

目前的结果：

A.new.new_method_1 # dictionary value 1
A.new.new_method_2 # dictionary value 2
A.new.new_method_3 # no superclass method `base_method' for A

如果你改变

class A
  prepend M

到

---

您将获得所需的输出

好的，因此这非常复杂，但它将按要求工作

class SomeLogic
  DICTIONARY = {
    new_method_1: 'dictionary value 1',
    new_method_2: 'dictionary value 2'
  }

  def initialize(method_name)
    @method_name = method_name
  end

  def call
    DICTIONARY[@method_name]
  end

end
module M

  def self.prepended(base)
    base.extend(ClassMethods)
  end

  def base_method(&block)
    SomeLogic.new(__callee__).call || 
    block&.call || # ruby < 2.3 block && block.call
    {}
  end

  module ClassMethods
    def method_added(method_name)
      if M.instance_methods.include?(method_name)
        orig = M.instance_method(method_name)
        M.remove_method(method_name)
        new = self.instance_method(method_name)
        self.prepend(Module.new do 
          define_method(method_name) do
            result = orig.bind(self).call(&new.bind(self))
          end   
        end)
        M.define_method(method_name, &orig.bind(M))  
      end
    end
  end

  alias_method :new_method_1, :base_method
  alias_method :new_method_2, :base_method
  alias_method :new_method_3, :base_method
  alias_method :new_method_4, :base_method
end

class A
  prepend M
  def new_method_3
    'foo'
  end
end

class B 
  prepend M 
end

如果您更喜欢

include

而不是

prepend

，那么

M

可能看起来像

module M 
  def self.included(base)
    super
    base.extend(ClassMethods)
  end

  def base_method
    if logic = SomeLogic.new(__callee__).call
      logic
    elsif self.class.instance_methods(false).include?(__callee__)
      send(__callee__,true)
    else
      {}
    end
  end
  module ClassMethods
    def method_added(method_name)
      return if @_adding_method # avoid stack level issues
      if M.instance_methods.include?(method_name)
        new = instance_method(method_name)
        @_adding_method = true # avoid stack level issues
        define_method(method_name) do |bypass_parent=false|
          return super() unless bypass_parent
          new.bind(self).call
        end   
        @_adding_method = false
      end
    end
  end
end

---

如果

SomeLogic:：DICTIONARY

具有

：new\u method\u 3

的键，则包含

将不起作用，因为此逻辑似乎需要优先于已定义的方法调用
p A.new.new_method_1 
#=> 'dictionary value 1'
p A.new.new_method_2 
#=> 'dictionary value 2'
p A.new.new_method_3 
#=> 'foo'
p A.new.new_method_4
#=> {}
p B.new.new_method_3
#=> {}

module M 
  def self.included(base)
    super
    base.extend(ClassMethods)
  end

  def base_method
    if logic = SomeLogic.new(__callee__).call
      logic
    elsif self.class.instance_methods(false).include?(__callee__)
      send(__callee__,true)
    else
      {}
    end
  end
  module ClassMethods
    def method_added(method_name)
      return if @_adding_method # avoid stack level issues
      if M.instance_methods.include?(method_name)
        new = instance_method(method_name)
        @_adding_method = true # avoid stack level issues
        define_method(method_name) do |bypass_parent=false|
          return super() unless bypass_parent
          new.bind(self).call
        end   
        @_adding_method = false
      end
    end
  end
end