extracting code to a module, failed

Dear all,

I wrote a piece of code with which I can copy models and their associated models as new database entries. Now I want to extract this code so I can easily use it in other projects/models. What I have:

class Foo < ActiveRecord::Base   cattr_accessor :non_duplicatable_columns   self.non_duplicatable_columns = [self.primary_key, 'created_at', 'updated_at','created_on', 'updated_on'] + self.column_names.select {| column_name| column_name =~ /_id$/}

  def copy     copy_columns = self.column_names - non_duplicatable_columns     a = Hash.new     copy_columns.each {|cc| a[cc] = self.send(cc) }     clone = self.create(a)   end end

Naively I thought I could copy-past this code in a module called Duplicatable and include that in Foo. This does not work. Ruby tells me that the file duplicatable.rb should define Duplicatable. Weird but I figured out that commenting out everything outside the def copy block makes it work. However now I lost the cattr_accessor and the initialisation of the non_duplicatable_columns.

I can place these two lines in an def init ... end but that requires me to do both the include Duplicatable and a call to init. Isn't there a nicer way of doing it?

With kind regards, Harm