IncrementalSequence.swift

class IncrementorSequence : SequenceType {
    
    func generate() -> GeneratorOf<Int> {
        var value = 0
        return GeneratorOf<Int> {
            return value++
        }
    }
}

let words = ["The", "quick", "brown", "fox"]

for (index, word) in zip(IncrementorSequence(), words) {
    println("index \(index) word \(word)")
}

for i in 0..<words.count {
    println("index \(i) word \(words[i])")
}

Thanks @regnerjr! That's exactly what I was looking for.