Sinatra-Extension-attr_accessor bug

require 'rubygems'
require 'sinatra/base'

module Sinatra
  module AttrAccessorBug
    
    # NB!! Using attr_accessor causes this error:
    #
    # SyntaxError: compile error (__DELEGATE__):2: syntax error, unexpected ',', expecting '=' ::Sinatra::Application.attr_accessor_bug_last=(*args, &b) ^
    #
    attr_accessor :attr_accessor_bug_first, :attr_accessor_bug_last
    
    # Whereas attr_reader works fine
    # attr_reader :attr_accessor_bug_first, :attr_accessor_bug_last
    
    def self.registered(app)
      # app.helpers AttrAccessorBug::Helpers
    end
  end
  
  register(Sinatra::AttrAccessorBug)
end


# ======================


# require 'sinatra/base'

class Hello < Sinatra::Base
  register Sinatra::AttrAccessorBug
  
  
  get '/' do
    "Hello World"
  end
  
end

Hello.run!