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PODataMapper has n with conditions
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  1. PODataMapper has n with conditions
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    copied!<p>By any chance is it possible to create a conditional association with DataMapper?</p> <p>For example:</p> <p>I want the User have n Apps just if that user have the attribute <code>:developer => true</code></p> <p>something like this:</p> <pre><code>class User include DataMapper::Resource property :id, Serial property :name, String, :nullable =&gt; false property :screen_name, String, :nullable =&gt; false, :unique =&gt; true property :email, String, :nullable =&gt; false, :unique =&gt; true, :format =&gt; :email_address property :password, BCryptHash, :nullable =&gt; false property :developer, Boolean, :default =&gt; false #The user just gets apps if developer has n :apps #,:conditions =&gt; "developer = 't'" end class App include DataMapper::Resource property :id, Serial property :name, String, :nullable =&gt; false belongs_to :user end </code></pre> <p>I know that this would be possible by creating a subclass from User as a Developer::User and in that class, use the <code>has n</code>, but I really would like to know if its possible to make it directly on the association declaration. </p> <p>Another way I also managed to do when using ARn was to extend the association and rewriting the methods for each action.</p> <p>So on the extension module I could have something like this:</p> <pre><code>module PreventDeveloperActions def new if proxy_owner.developer? super else raise NoMethodError, "Only Developers can create new applications" end end # and so on for all the actions ... end </code></pre> <p>But again, I really would like to avoid the use of this solutions if possible, but just if it's possible to perform a quick and direct method easily with DataMapper :)</p> <p>Thanks in advance</p>
 

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