gistfile1.m

-(NSIndexSet *) lookupAll: (NSString *) theName
{
  NSIndexSet *result = [book indexOfObjectsPassingTest:
    ^(id obj, NSUInteger idx, BOOL *stop)
    {
      if ([[obj name] caseInsensitiveCompare: theName] ==
         NSOrderedSame)
           return YES;  // found a match, keep going
      else
           return NO;   // keep looking
    }];
  // Return the result
  return result;
}