How can I remove or replace all punctuation characters from a String?

Question

I have a string composed of words, some of which contain punctuation, which I would like to remove, but I have been unable to figure out how to do this.

For example if I

Answer 1

NSScaner way:

let words = "Hello, this : is .. a  string?"

//
let scanner = NSScanner(string: words)
var wordArray:[String] = []
var word:NSString? = ""

while(!scanner.atEnd) {
  var sr = scanner.scanCharactersFromSet(NSCharacterSet(charactersInString: "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKMNOPQRSTUVWXYZ"), intoString: &word)
  if !sr {
    scanner.scanLocation++
    continue
  }
  wordArray.append(String(word!))
}

println(wordArray)