public static bool uksort(Context ctx /*, caller*/, [In, Out] PhpArray array, IPhpCallable compare) { if (array == null) { //PhpException.ReferenceNull("array"); //return false; throw new ArgumentNullException(); } if (!PhpVariable.IsValidCallback(compare)) return false; array.Sort(new KeyComparer(new PhpUserComparer(ctx, compare), false)); return true; }