 
 extension sockaddr_in6: SocketAddress {
   
-  public static var domain = AF_INET6
-  public static var size   = __uint8_t(strideof(sockaddr_in6))
+  public static let domain = AF_INET6
+  public static let size   = __uint8_t(strideof(sockaddr_in6))
   
   public init() {
 #if os(Linux) // no sin_len on Linux

  // TBD: sockaddr_un would be interesting as the size of the structure is
  //      technically dynamic (embedded string)
  
  public static var domain = AF_UNIX
  public static var size   = __uint8_t(strideof(sockaddr_un)) // CAREFUL
  
  public init() {
#if os(Linux) // no sin_len on Linux


extension sockaddr_in: SocketAddress {
  
  public static let domain = AF_INET
  public static let size   = __uint8_t(strideof(sockaddr_in))
    // how to refer to self?
  
  public init() {
