Swift: What's the best way to pair up elements of an Array

Question

I came across a problem that required iterating over an array in pairs. What\'s the best way to do this? Or, as an alternative, what\'s the best way of transforming an Array

Answer 1

You don't need a custom type, like PairIterator as the above answers prescribe. Getting a paired sequence is a one-liner:

let xs = [1, 2, 3]
for pair in zip(xs, xs.dropFirst()) {
    print(pair) // (1, 2) (2, 3)
}

If you intend to reuse that, you can place a pairs method inside an extension:

extension Sequence {
    func pairs() -> AnySequence<(Element, Element)> {
        AnySequence(zip(self, self.dropFirst()))
    }
}