Question

This code works fine, but each time i look at it, i die a little bit inside. 🙁

Can you help me streamline it a bit?

Is there a more elegant way to .append(SomeString)? (To give you some perspective, code prints elements of the Linked List)

- (NSString *) description {      
    Node* tempNode = [self firstNode];

    if (tempNode == nil) {
        return @"List contains no elements";
    }

    NSString *desc= [[NSString alloc] initWithString:@"(null) -- "];
    desc = [desc stringByAppendingString:[firstNode nodeCharacter]];
    desc = [desc stringByAppendingString:@" -- "];

    while ([tempNode nextNode] != nil) {
        desc =  [desc stringByAppendingString:[[tempNode nextNode]nodeCharacter]];
        desc =  [desc stringByAppendingString:@" -- "];
        tempNode = [tempNode nextNode];
    }

    return [desc stringByAppendingString:@" (null)"];


}

Answer 1

• First of all, if you want to build a string step by step or modify it, stop using stringByAppendingString:, and use NSMutableString instead of NSString !!!

• Then, for your matter, you can even use stringWithFormat: to build part of your string.

• Finally, you forgot to manage your memory: you alloc/init your string but never release it (and as your reassign the desc variable the line after, you loose track of the allocated memory and have a leak.

So here is the revised code:

- (NSString *) description {      
  Node* tempNode = [self firstNode];

  if (tempNode == nil) {
    return @"List contains no elements";
  }

  NSMutableString *desc = [NSMutableString stringWithFormat:@"(null) -- %@ -- ",[firstNode nodeCharacter]];
  while ((tempNode = [tempNode nextNode]) != nil) {
    [desc appendFormat:@"%@ -- ",[tempNode nodeCharacter]];
  }
  [desc appendingString:@" (null)"];

  return desc;
}

(Note that you may also build an NSArray of the nodes of your list and use componentsJoinedByString then at the end… so you have multiple possibilities here anyway)