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PORails: rendering a collection after an object in that collection fails validation
 

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  1. PORails: rendering a collection after an object in that collection fails validation
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    <p>Let's say I have the following models</p> <p><strong>models/user.rb</strong></p> <pre><code>class User has_many :degrees end </code></pre> <p><strong>models/degree.rb</strong></p> <pre><code>class Degree attr_accessible :name belongs_to :user validates :name, :presence =&gt; true end </code></pre> <p>Within <code>Users#show</code> I want to display the users degrees and provide a form for creating a new one.</p> <p><strong>views/users/show.html.erb</strong></p> <pre><code>... Your current degrees: &lt;%= render @user.degrees %&gt; Add a new degree: &lt;%= form_for Degree.new do |f| %&gt; &lt;%= f.text_field :name %&gt; &lt;%= f.submit "Submit" %&gt; &lt;% end %&gt; ... </code></pre> <p><strong>views/degrees/_degree.html.erb</strong></p> <pre><code>... &lt;%= degree.name %&gt; </code></pre> <p>So inside degrees_controller.rb we have</p> <p><strong>controllers/degrees_controller.rb</strong></p> <pre><code>class DegreesController &lt; ApplicationController # ... def create degree = current_user.degrees.build(params[:degree]) if degree.save redirect_to # somewhere with a flash message else render "users#show" end end end </code></pre> <p>The problem with this is in the call to <code>render @user.degrees</code> inside <code>views/users/show.html.erb</code> after a degree has failed validation. If I submit the form without providing a name, the degree object persists in memory after the <code>render</code> method is called, and will render the <code>views/degrees/_degree.html.erb</code> partial for the invalid object. This partial calls the <code>name</code> method, which throws a Nil error.</p> <p>I can throw conditionals in the view (i.e., <code>unless degree.name.nil?</code>), but this smells to me. If the attributes on the degree object grow, that partial will contain way too much conditional logic.</p> <p>Any thoughts?</p>
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    1. USFeech
    1. USFeech
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    1. COplease add source of views/degrees/_degree.html.erb , and full error message
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      1. PORails: rendering a collection after an object in that collection fails validation
      1. USFivell
    2. COThis is the kind of thing you could use nested attributes and fields_for, have a look into those.
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      1. PORails: rendering a collection after an object in that collection fails validation
      1. USMatt
    3. CO@Fivell, I added part of the `_degree.html.erb` view to illustrate the problem. @Matt, I thought about looking into nested attributes, but chose not to go that route right now. Thanks.
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      1. USFeech
 

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