From: Pit Capitain <pit.capitain@...>
Date: 2007-07-26T01:25:44+09:00
Subject: Re: Bidirectionnal relation

2007/7/24, dohzya <dohzya@gmail.com>:
> I have a problem with bidirectional relations : how to implements it ?
> (...)
> If anyone has a suggestion (solution or link or anything) to implement
> transparent bidirectional relation... :)

Hi Etienne,

in ruby-talk:121602 I posted a little library to implement this.
Here's your example:

  require "relation"

  class Entity
  end

  Relation.new Entity, :one, :mother, Entity, :many, :daughters

  a = Entity.new
  b = Entity.new

  a.mother = b
  puts(b.daughters.include?(a))  # => true

  a.daughters << b
  puts(b.mother == a)            # => true


If you find nothing else maybe I should create my first gem...

Regards,
Pit