gistfile1.swift

extension Array {
    func each(closure: ((item: T, idx: Int) -> Void)) {
        var idx : Int = 0
        for item in self {
            closure(item: item, idx: idx)
            
            idx += 1
        }
    }
}
....

Variant 1:

var arr = [1, 2, 3]
arr.each {
  println("Value: \($0)")
}

Output: 

Value: (1, 0)
Value: (2, 1)
Value: (3, 2)


Variant 2:

var arr = [1, 2, 3]
arr.each {
    println("Value: \($0) Index: \($1)")
}

Value: 1 Index: 0
Value: 2 Index: 1
Value: 3 Index: 2


Variant 3:

var arr = [1, 2, 3]
arr.each { (item, idx) in
    println("Value: \(item)")
}

Output:

Value: 1
Value: 2
Value: 3