Problem with extension

extension-example.swift

extension Int {
    func times(block: () -> ()) {
        for _ in 0..self { block() }
    }
    func times(block: (Int) -> ()) -> Int {
        for i in 0..self { block(i) }
        return self
    }
}

3.times { println("welcome") }


4.times { i in println("by \(i)") } // => Ambigious use of 'times'

// fix:

4.times { (i:Int) in println("by \(i)") }