Just temporarily storing some code examples:

- (NSArray *)tokensSeparatedByCharactersFromSet:(NSCharacterSet *)separatorSet
{
  NSScanner      *scanner      = [NSScanner scannerWithString:self];
  NSCharacterSet *tokenSet     = [separatorSet invertedSet];
  NSMutableArray *tokens       = [NSMutableArray array];

  [scanner setCharactersToBeSkipped:separatorSet];

  while (![scanner isAtEnd])
  {
    NSString  *destination = [NSString string];

    if ([scanner scanCharactersFromSet:tokenSet intoString:&destination])
    {
      [tokens addObject:[NSString stringWithString:destination]];
    }
  }

  return [NSArray arrayWithArray:tokens];
}

- (NSArray *)objCTokens
{
  NSMutableCharacterSet *tokensSet = [NSMutableCharacterSet alphanumericCharacterSet];
  [tokensSet addCharactersInString:@"_:"];
  return [self tokensSeparatedByCharactersFromSet:[tokensSet invertedSet]];
}

-(NSString *)removeTabsAndReturns
{
    NSMutableString *outputString = [NSMutableString string];
    NSCharacterSet *charSet;
    NSString *temp;

    NSScanner *scanner = [NSScanner scannerWithString:self];

    charSet = [NSCharacterSet characterSetWithCharactersInString:@"\n\r\t"];

    while ([scanner scanUpToCharactersFromSet:charSet intoString:&temp])
      {
	[outputString appendString:temp];

      }
    return [[outputString copy] autorelease];
}