Iterating over an NSOrderedSet

Question

I\'m trying to iterate over an instance of NSOrderedSet. Something like this:

func myFunc() {
    var orderedSet = NSOrderedSet(array: [ 42, 43, 44])

    for n          


        

Answer 1

The Swifty, simplest, and most general solution would be to shallow copy to an array in O(1) - per the docs. This would allow you to use Swift's other functional techniques and functions.

import Swift
import Foundation


println("Simplest, most accessible, O(1) performance: shallow copy to array:")

var set = NSOrderedSet(array: map(0...7) { d in d })
for d in set.array as [Int] {
    print("\t\(d)")
}

println("\n\nIn general - for other types and cases, you could create a sequence:")

extension NSOrderedSet {
    func sequenceOf(t:T.Type) -> SequenceOf {
        var current = 0
        return SequenceOf(GeneratorOf({ () -> T? in
            return current < self.count ? self.objectAtIndex(current++) as? T : nil
        }))
    }
}

for d in set.sequenceOf(Int.self) {
    print("\t\(d)")
}

Simplest, most accessible, O(1) performance: shallow copy to array:

0 1 2 3 4 5 6 7

In general - for other types and cases, you could create a sequence:

0 1 2 3 4 5 6 7