arr&[-1] array accessor that checks if index is out of range, and returns an optional....

gistfile1.txt

let arr = [1,2,3,4]


func & <T>(lhs:Array<T>,rhs:[Int]) -> T?{
    guard let index = rhs.first else{
        print("no index!")
        return nil
    }
    if index < 0{
        print("negative index")
        return nil
    }
    if index >= lhs.count{
        print("index \(index) out of range 0-\(lhs.count-1)")
        return nil
    }
    return lhs[index]
}


let x = arr&[-1] //nil
let y = arr&[10] //nil
let z = arr&[ 0] //1


func randomIndex(index:Int)->Int?{
    
    guard let res = arr&[index] else {
        print("something went terribly wrong...")
        return nil
    }
    
    return res
}