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

I don't think this is any better than Martin R's, but seems the OP needs something else...

struct PairIterator: IteratorProtocol {
    private var baseIterator: C
    init(_ iterator: C) {
        baseIterator = iterator
    }

    mutating func next() -> (C.Element, C.Element)? {
        if let left = baseIterator.next(), let right = baseIterator.next() {
            return (left, right)
        }
        return nil
    }
}
extension Sequence {
    var pairs: AnySequence<(Self.Iterator.Element,Self.Iterator.Element)> {
        return AnySequence({PairIterator(self.makeIterator())})
    }
}

input.pairs.forEach{ print($0) }

let output = input.pairs.map{$0}
print(output) //->[(1, 2), (3, 4), (5, 6)]