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POWhy does this class inheritance cause an infinite recursion
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copied!<p>I'm attempting to DRY up decorators in a Rails project.</p> <p>Essentially, I want to delegate any missing methods to the resource object (or the resource object's class).</p> <p>Here's a simplified example</p> <pre><code># Decorator base class class Decorator attr_accessor :resource private def method_missing(name, *args, &block) self.resource.send(name, *args, &block) end # infinite recursion happens here def self.method_missing(name, *args, &block) self.resource.class.send(name, *args, &block) end end # Decorator class that will be used class UserCreator < Decorator attr_reader :user def initialize(params) @user = User.new(params[:user]) self.resource = @user end def save # do special stuff with user object if @user.save # perhaps do some more stuff after the save true else # perhaps handle the error here false end end end # A simple controller example class SomeController < ApplicationController respond_to :json def create @user = UserCreator.new(params) if @user.save render :json => @user else render :json => @user.errors end end end </code></pre> <p>However, in the class <code>Decorator</code> an infinite recursion happens in the class (singleton) method <code>self.method_missing</code>. It's passing <code>resource</code> as the <code>name</code> argument in that method.</p> <p>I am trying to wrap my head around the control flow of what's going on here. A method <code>resource</code> exists in the base <code>Decorator</code> class via <code>attr_accessor</code>, so I thought, the subclass <code>UserCreator</code> also has this method. So I'm not sure why it thinks <code>resource</code> is a missing method. If I get rid of the <code>Decorator</code> superclass and just implement the <code>method_missing</code>s in the <code>UserCreator</code> class, all works as expected.</p> <p>Any help in implementing this base class to work as expected is greatly appreciated, so I don't have to implement the same <code>method_missing</code> methods in every decorator.</p>

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