[Question] using Map, setCompareFunction, ordering lists

[Norberto Eiji Nawa]

Hello everybody,

I am trying to construct an ordered list (sellList), using my own
comparison function (comparePrice), as below:

(...)
sellList = [Map createBegin: [self getZone]];
// Set the comparison function
[sellList setCompareFunction: comparePrice];
sellList = [sellList createEnd];
(...)

where comparePrice is defined as:

int comparePrice(id c1, id c2) {

  int out1, out2;
  
  out1 = [c1 getPrice];
  out2 = [c2 getPrice];
  printf("out1:%d out2:%d\n", out1, out2);

  if (out1 == out2)
    return 0;

  if (out1 < out2)
    return -1;

  return 1;
}

The problem is that I am getting a segmentation fault in [c1
getPrice], when sellList contains already one element.

I feel I am missing something here...

[newbie question]: do I have to care about having c1 and c2 pointing
to the right objects? Or c1/c2 is the object already in the list and
c1/c2 is the new object to be inserted? Or am I really missing the
point here?

Thanks a lot for your patience,

Eiji


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