Question

I have tokenized an NSString into an NSMutable Array. I can then use an NSSortDescriptor to sort that array by the length of its strings. Then I can perform methods on certain words starting from the longest.

This is where my problem surfaces. I now need to restore the original sort order of the array so that I can run the array back into an edited string.

Answer 1

My answer is essentially like Steve’s except that I’d do it the other way around — keep the original array, create a sorted copy of that, step through the sorted copy doing your processing and then throw it away. So, e.g.

NSArray *yourOriginalArray = ...whatever...;

// do processing
for(id object in [yourOriginalArray sortedArrayUsing<whatever means>])
{
    // if you're doing processing that doesn't change the identity of
    // the object then there's no need to worry about this, but supposing
    // you want to adjust the identity (eg, the source array is full of
    // immutable objects and you want to replace them) then...

    NSUInteger originalIndex = [yourOriginalArray indexOfObject:object];

    id replacementObject = [self mutatedFormOf:object];
    [yourOriginalArray replaceObjectAtIndex:originalIndex
                     withObject:replacementObject];
    // of course, this is only if yourOriginalArray is mutable
}