title: erb: Using each_with_index on a link_to id string
body: <p>How can I add the variable <em>i</em> in the id tag on link_to such as this:</p>
  
  <pre><code>&lt;% @tips.each_with_index do |tip, i| %&gt;
  &lt;%= link_to "Flag me", flag_path, method: :put, remote: true, id: "flag_&lt;i goes here&gt;" %&gt;
  &lt;% end %&gt;
  </code></pre>
  
  <p>When using an html code, I can just do this:</p>
  
  <pre><code>&lt;a href="/path" id="flag_&lt;%= i %&gt;"&gt; Flag me &lt;/a&gt;
  </code></pre>
  
  <p>I am not sure how to insert a variable inside the erb id tag.</p>