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POHow does has_one :through work?
 

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  1. POHow does has_one :through work?
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    <p>I have three models:</p> <pre><code>class ReleaseItem &lt; ActiveRecord::Base has_many :pack_release_items has_one :pack, :through =&gt; :pack_release_items end class Pack &lt; ActiveRecord::Base has_many :pack_release_items has_many :release_items, :through=&gt;:pack_release_items end class PackReleaseItem &lt; ActiveRecord::Base belongs_to :pack belongs_to :release_item end </code></pre> <p>The problem is that, during execution, if I add a pack to a release_item it is not aware that the pack is a pack. For instance:</p> <pre><code>Loading development environment (Rails 2.1.0) &gt;&gt; item = ReleaseItem.new(:filename=&gt;'MAESTRO.TXT') =&gt; #&lt;ReleaseItem id: nil, filename: "MAESTRO.TXT", created_by: nil, title: nil, sauce_author: nil, sauce_group: nil, sauce_comment: nil, filedate: nil, filesize: nil, created_at: nil, updated_at: nil, content: nil&gt; &gt;&gt; pack = Pack.new(:filename=&gt;'legion01.zip', :year=&gt;1998) =&gt; #&lt;Pack id: nil, filename: "legion01.zip", created_by: nil, filesize: nil, items: nil, year: 1998, month: nil, filedate: nil, created_at: nil, updated_at: nil&gt; &gt;&gt; item.pack = pack =&gt; #&lt;Pack id: nil, filename: "legion01.zip", created_by: nil, filesize: nil, items: nil, year: 1998, month: nil, filedate: nil, created_at: nil, updated_at: nil&gt; &gt;&gt; item.pack.filename NoMethodError: undefined method `filename' for #&lt;Class:0x2196318&gt; from /usr/local/lib/ruby/gems/1.8/gems/activerecord-2.1.0/lib/active_record/base.rb:1667:in `method_missing_without_paginate' from /usr/local/lib/ruby/gems/1.8/gems/mislav-will_paginate-2.3.3/lib/will_paginate/finder.rb:164:in `method_missing' from /usr/local/lib/ruby/gems/1.8/gems/activerecord-2.1.0/lib/active_record/associations/association_collection.rb:285:in `send' from /usr/local/lib/ruby/gems/1.8/gems/activerecord-2.1.0/lib/active_record/associations/association_collection.rb:285:in `method_missing_without_paginate' from /usr/local/lib/ruby/gems/1.8/gems/activerecord-2.1.0/lib/active_record/base.rb:1852:in `with_scope' from /usr/local/lib/ruby/gems/1.8/gems/activerecord-2.1.0/lib/active_record/associations/association_proxy.rb:168:in `send' from /usr/local/lib/ruby/gems/1.8/gems/activerecord-2.1.0/lib/active_record/associations/association_proxy.rb:168:in `with_scope' from /usr/local/lib/ruby/gems/1.8/gems/activerecord-2.1.0/lib/active_record/associations/association_collection.rb:281:in `method_missing_without_paginate' from /usr/local/lib/ruby/gems/1.8/gems/mislav-will_paginate-2.3.3/lib/will_paginate/finder.rb:164:in `method_missing' from (irb):5 &gt;&gt; </code></pre> <p>It seems that I should have access to item.pack, but it is unaware that the pack is a Pack item.</p>
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