anchor.diff:  
   final indexedLibraries = new Set<LibraryElement>();
   final searchIndex = new SimpleTrie<List<Element>>();
  +
  +final _A = 'A'.codeUnitAt(0);
  +final _Z = 'Z'.codeUnitAt(0);
  +final _0 = '0'.codeUnitAt(0);
  +final _9 = '9'.codeUnitAt(0);
   
   void _indexLibrary(LibraryElement library) {
     library.traverse((Element element) {
  
positive.code:  * Search Result matching an node in the AST.
   */
  class SearchResult implements Comparable {
    /** [Element] this search result references. */
    Element element;
    /** Score of the search result match. Higher is better. */
    num score;
  
  
negative.code:         // TODO(jacobr): this formula is primitive. We should order by
          // popularity and the number of words into the match instead.
          // Also prioritize base classes over subclasses when sorting(?)
          num score = -name.indexOf(query) - (element.name.length * 0.001);
          if (element is LibraryElement) score += 200;
          if (element is ClassElement) score += 100;
          if (name == query) score += 1000;
  