anchor.diff:  /**
    * Returns a String tag identifying the type of the native object, or `null`.
    * The tag is not the name of the type, but usually the name of the JavaScript
  - * constructor function.
  + * constructor function.  Initialized by [initHooks].
    */
   Function getTagFunction;
   
  
positive.code:     return tag;
    }
  
    hooks.getTag = getTagIE;
  }''');
  
  
  
negative.code:  * If a lookup via [getTagFunction] on an object [object] that has [tag] fails,
   * this function is called to provide an alternate tag.  This allows us to fail
   * gracefully if we can make a good guess, for example, when browsers add novel
   * kinds of HTMLElement that we have never heard of.  Initialized by
   * [initHooks].
   */
  Function alternateTagFunction;
  
  /**
   * Returns the prototype for the JavaScript constructor named by an input tag.
   * Returns `null` if there is no such constructor, or if pre-patching of the
   * constructor is to be avoided.  Initialized by [initHooks].
   */
  Function prototypeForTagFunction;
  
  
  String toStringForNativeObject(var obj) {
  