static CharSequence virtualToUpper(CharSequence s) {
  if (s == null) null;
  int l = s.length();
  ret new CharSequence {
    public int length() { ret l; }
    public char charAt(int i) ctex { ret upper(s.charAt(i)); }
    public CharSequence subSequence(int from, int to) { ret substringObject(this, from, to); }
    toString { ret charSequenceToStringByChar(this); }
  };
}