rails many to many self join

Question

could some one point me to the right direction:

I try to build a model for rails that build up the following:

ClassA -id

ClassA has a relation to

Answer 1

If it doesn't make too much sense to create another class to join the two, an alternative approach could be:

class Word < ActiveRecord::Base 
  has_and_belongs_to_many :synonyms, class_name: "Word", 
                                     join_table: "word_synonyms",
                                     association_foreign_key: "synonym_id"
end

The join table would look like this:

create_table :word_synonyms do |t|
  t.integer :word_id
  t.integer :synonym_id
end