String.scan ...

gistfile1.swift

import Cocoa

extension String {
  func scan(regex: String) -> [String] {
    let regex = NSRegularExpression(pattern: regex,
                                    options: nil, error: nil)!
    let nsString = self as NSString
    let results = regex.matchesInString(self, options: NSMatchingOptions(0), range: NSMakeRange(0, (self as NSString).length))
        as! [NSTextCheckingResult]
    return map(results) { nsString.substringWithRange($0.range)}
  }
}

let x = "Hello World".scan("l")
println(x.count)