anchor.diff:  
       var $tree = $('#jstree_demo');
   
  +    var params_func = function()
  +    {
  +      var params = {filters: {}};
  +
  +      if ($('form#options input[name="stackprofiler_elision"]').is(':checked')) params.filters.stackprofiler_elision = {};
  +      if ($('form#options input[name="remove_gems"]').is(':checked')) params.filters.remove_gems = {};
  +      if ($('form#options input[name="quick_method_elision"]').is(':checked')) params.filters.quick_method_elision = {};
  +      if ($('form#options input[name="compress_tree"]').is(':checked')) params.filters.compress_tree = {};
  +
  +      return params;
  +    };
  +
       var load_func = function(node, cb) {
  -      var params = {
  -        filters: {
  -          stackprofiler_elision: {},
  -          remove_gems: {},
  -          quick_method_elision: {},
  -          compress_tree: {}
  -        }
  -      };
  -      $.post("/__stackprofiler/json?run_id=<%= @run_id %>", JSON.stringify(params), function(data, status, xhr) {
  +      $.post("/__stackprofiler/json?run_id=<%= @run_id %>", JSON.stringify(params_func()), function(data, status, xhr) {
           cb.call(this, data);
         });
       };
  
positive.code:       <% end %>
      </ul>
    </li>
  <% end %>
  
  <div id="foo" style="">
  
negative.code:     });
  
      $tree.on("changed.jstree", function (e, data) {
        if (!data.node) return;
  
        var addrs = data.node.data.addrs;
        var url = "/__stackprofiler/code/" + addrs[0] + "?run_id=<%= @run_id %>";
        $("#source-display").load(url);
      });
  
      $('button#save-options').click(function() {
        $tree.jstree().refresh();
      });
    });
  </script>
  
  <div id="options-modal" class="modal">
    <div class="modal-dialog">
      <div class="modal-content">
        <div class="modal-header">
          <button type="button" class="close" data-dismiss="modal" aria-hidden="true">×</button>
          <h4 class="modal-title">Stackprofiler Options</h4>
        </div>
        <div class="modal-body">
          <form id="options" class="form-horizontal">
            <fieldset>
              <div class="checkbox">
                <label>
                  <input type="checkbox" name="remove_gems"> Remove gems
                </label>
              </div>
              <div class="checkbox">
                <label>
                  <input type="checkbox" name="quick_method_elision"> Remove quick methods
                </label>
              </div>
              <div class="checkbox">
                <label>
                  <input type="checkbox" name="stackprofiler_elision"> Remove top of stack
                </label>
              </div>
              <div class="checkbox">
                <label><input type="checkbox" name="compress_tree"> Compress stack
                </label>
              </div>
            </fieldset>
          </form>
        </div>
        <div class="modal-footer">
          <button type="button" class="btn btn-default" data-dismiss="modal">Close</button>
          <button type="button" class="btn btn-primary" data-dismiss="modal" id="save-options">Apply</button>
        </div>
      </div>
    </div>
  </div>
  