title: event passed to debounce firing continuously (not debouncing)
body: <p>Here's the code:</p>
  
  <pre><code>lookup_book = (obj) -&gt;
    $.get '/list_items/retrieve_google_book/' + obj.val() + '/' + obj.attr("id")
    return
  
  delayed_lookup = (obj) -&gt;
    _.debounce(lookup_book(obj), 3000)
    return
  
  $(document).on 'keyup', '.list-item-title', (event) -&gt;
    delayed_lookup($(this))
    return
  </code></pre>
  
  <p>I want lookup_book and therefore the ajax request to only fire if the user has not typed for 3000ms. Right now it fires as I am typing the letters in the input field, without any sort of delay.</p>
  
  <p>What's going on here? I'm pulling my hairs out.</p>