title: Ruby on Rails Form For with two parameters
body: <p>I have the following code but I am not able to understand hows does routing happen for form_for([@article, @article.comments.build]).
          <p>
            <strong>Title:</strong>
            &lt;%= @article.title %>
          </p></p>
  
  <pre><code>    &lt;p&gt;
        &lt;strong&gt;Text:&lt;/strong&gt;
        &lt;%= @article.text %&gt;
      &lt;/p&gt;
  
      &lt;h2&gt;Add a comment:&lt;/h2&gt;
      &lt;%= form_for([@article, @article.comments.build]) do |f| %&gt;
        &lt;p&gt;
          &lt;%= f.label :commenter %&gt;&lt;br&gt;
          &lt;%= f.text_field :commenter %&gt;
        &lt;/p&gt;
        &lt;p&gt;
          &lt;%= f.label :body %&gt;&lt;br&gt;
          &lt;%= f.text_area :body %&gt;
        &lt;/p&gt;
        &lt;p&gt;
          &lt;%= f.submit %&gt;
        &lt;/p&gt;
      &lt;% end %&gt;
  
      &lt;%= link_to 'Back', articles_path %&gt;
      | &lt;%= link_to 'Edit', edit_article_path(@article) %&gt;
  </code></pre>