Question

will a fast enumeration of an array always go in index order?

for (NSDictionary *zone in myArray)
{
    //do code
}

will that always enumerate from index location 0, 1, 2, …, n?

i prefer fast enumeration over a standard for loop since it makes the code easier to read.

Answer 1

Yes it will:

For collections or enumerators that have a well-defined order—such as
an NSArray or an NSEnumerator instance derived from an array—the
enumeration proceeds in that order, so simply counting iterations
gives you the proper index into the collection if you need it.

docs here