anchor.diff:                return _limitedDiffFromVersion(diff);
               }
   
  -            return pretify(diff);
  +            return _prettify(diff);
       }).catchError((e){
        if (e is List) {
          return e;
  
positive.code:         });
    }
  
    Future remove(String _id, String author) {
      cache.invalidate();
      num nextVersion;
      return _get_locks().then((_) => _maxVersion).then((version) {
  
negative.code:       ).then((_) => _release_locks()).then((_) => nextVersion);
    }
  
    Future<Map> diffFromVersion(num version) {
      return cache.putIfAbsent('version ${collection.collectionName}', () => _maxVersion)
        .then((maxVer) {
  