text: //----------------------------------------------------------------------------
  //  Copyright (C) 2012  The IPython Development Team
  //
  //  Distributed under the terms of the BSD License.  The full license is in
  //  the file COPYING, distributed as part of this software.
  //----------------------------------------------------------------------------
  
  //============================================================================
  //CellToolbar Example
  //============================================================================
  
  /**
   * $.getScript('/static/js/celltoolbarpresets/slideshow.js');
   * ```
   * or more generally  
   * ```
   * $.getScript('url to this file');
   * ```
   */
   // IIFE without asignement, we don't modifiy the IPython namespace
  (function (IPython) {
      "use strict";
  
      var CellToolbar = IPython.CellToolbar;
      var slideshow_preset = [];
  
      var select_type = CellToolbar.utils.select_ui_generator([
              ["-"            ,undefined      ],
              ["Slide"        ,"slide"        ],
              ["Sub-Slide"    ,"subslide"     ],
              ["Fragment"     ,"fragment"     ],
              ["Skip"         ,"skip"         ],
              ["Notes"        ,"notes"        ],
              ],
              // setter
              function(cell, value){
                  // we check that the slideshow namespace exist and create it if needed
                  if (cell.metadata.slideshow == undefined){cell.metadata.slideshow = {}}
                  // set the value
                  cell.metadata.slideshow.slide_type = value
                  },
              //geter
              function(cell){ var ns = cell.metadata.slideshow;
                  // if the slideshow namespace does not exist return `undefined`
                  // (will be interpreted as `false` by checkbox) otherwise
                  // return the value
                  return (ns == undefined)? undefined: ns.slide_type
                  },
              "Slide Type");
  
      CellToolbar.register_callback('slideshow.select',select_type);
  
      slideshow_preset.push('slideshow.select');
  
      CellToolbar.register_preset('Slideshow',slideshow_preset);
      console.log('Slideshow extension for metadata editing loaded.');
  
  }(IPython));
  