// Try to get the quoting right...

static S smartJoin(S[] args) {
  if (args.length == 1) return args[0];
  
  S[] a = new S[args.length];
  for (int i = 0; i < a.length; i++)
    a[i] = !isJavaIdentifier(args[i]) && !isQuoted(args[i]) ? quote(args[i]) : args[i];
  return join(" ", a);
}