Swift Cannot Assign to immutable value of type NSData

Question

I have

let data = NSData(bytes: &positionValue, length: sizeof(UInt8))

and

let dataString=NSString(bytes: &data, length: sizeof(UInt8), encoding: NSUTF8StringEncoding)

Unfortunately the compiler throws an error at the second line, saying that it can't assign to immutable value of type NSData. How would I go about converting my original data variable to a string with encoding SUTF8StringEncoding?

Answer 1

update: Xcode 7.2 • Swift 2.1.1

let myTestString = "Hello World"

// converting from string to NSData
if let myStringData = myTestString.dataUsingEncoding(NSUTF8StringEncoding) {

    // converting from NSData to String
    let myStringFromData = String(data: myStringData, encoding: NSUTF8StringEncoding) ?? "Hello World"
}