Differences between [NSArray arrayWithArray:] and [NSArray copy]

Question

lately I work much with arrays and I\'m wonder.. what\'s diffrences between those two lines.

NSArray *array = [NSArray arrayWithArray:someArray];

Answer 1

The difference between the two is that the latter will be retained. The former will be autoreleased.

Both versions make a shallow copy of the array.

NSMutableArray *notMutableReally = [NSArray arrayWithArray:aMutableArray];

Should give you a compiler warning as you will be trying to assign a NSArray to a NSMutableArray.

Use.

NSMutableArray *mutableArrayCopy = [NSMutableArray arrayWithArray:aMutableArray];

Which is faster? Dont worry, they are all far faster than the rest of the stuff you will be doing. Check with Instruments if you really care.