我正在尝试编写一个通用模块,将dynamic_missing模式应用于我的一些Rails模型中.这些模型具有类方法和实例方法.虽然我可以相当直接地为类案例编写一个模块：
module ClassVersion
extend ActiveSupport::Concern
module ClassMethods
def method_missing(meth,*args,&block)
if meth.to_s =~ /^(.+)_async$/
Async::handle_async self,$1,&block
else
super meth,&block
end
end
# Logic for this method MUST match that of the detection in method_missing
def respond_to_missing?(method_name,include_private = false)
Async::async?(method_name) || super
end
end
end
或实例案例：
module InstanceVersion
extend ActiveSupport::Concern
def method_missing(meth,&block)
if meth.to_s =~ /^(.+)_async$/
Async::handle_async self,&block
else
super meth,&block
end
end
# Logic for this method MUST match that of the detection in method_missing
def respond_to_missing?(method_name,include_private = false)
Async::async?(method_name) || super
end
end
……我似乎无法在同一个班级支持这两种情况.有没有更好的方法来覆盖method_missing,以便支持这两种情况？我在Rails 3.2上….
解决方法
你想要达到的目标非常简单,同时又不同寻常. ActiveSupport :: Concern让您可以定义嵌套的ClassMethods模块,该模块在包含的模块挂钩上扩展基类.通常这很方便,因为您不希望使用相同的方法扩充类及其实例.
您需要做的是停止使用ActiveSupport :: Concern并编写包含的钩子以满足您的特定需求：
module AsyncModule
def method_missing(meth,&block)
if meth.to_s =~ /^(.+)_async$/
Async::handle_async self,&block
else
super meth,&block
end
end
# Logic for this method MUST match that of the detection in method_missing
def respond_to_missing?(method_name,include_private = false)
Async::async?(method_name) || super
end
private
def self.included(base)
base.extend self
end
end