Swift2 came out yesterday! For free! I thought that Swift2 would have built-in support for I/O, but it looks like you need to import Cocoa first.
import Cocoa
let data = NSString( string:"Hallo, Welt!" )
let destPath = "/Users/connorjohnson/myFile.txt"
var filemgr = NSFileManager.defaultManager()
do {
try data.writeToFile(destPath, atomically: true, encoding: NSUTF8StringEncoding)
} catch let error as NSError {
print("Error: \(error)")
}