sclass ManagedString extends AbstractManagedObject implements CharSequence {
  replace Addr with int.
  
  S value;
  
  // usable but doesn't handle null
  *(ManagedIntObjects_v1 mem, Addr *addr) {
    super(mem);
    value = mem.readString(addr);
  }
  
  // ...unless you call this
  bool isNull() { ret value == null; }
  
  // internal
  *(ManagedIntObjects_v1 mem, S *value, Addr *addr) {
    super(mem);
  }
  
  // for proper null handling
  static ManagedString load(ManagedIntObjects_v1 mem, Addr addr) {
    S value = mem.readString(addr);
    if (value == null) null;
    ret new ManagedString(mem, value, addr);
  }
  
  static ManagedString create(ManagedIntObjects_v1 mem, S value) {
    if (value == null) null;
    ret new ManagedString(mem, value, mem.newString(value));
  }

  // GC handling
  public void scanForCollection(IManagedObjectCollector gc) {
    gc.noteString(addr, lambda1 setAddr);
  } 
  
  @Override
  public char charAt(int index) {
    ret value.charAt(index);
  }

  @Override
  public int length() {
    ret l(value);
  }

  @Override
  public CharSequence subSequence(int start, int end) {
    ret value.substring(start, end);
  }

  @Override
  toString { ret value == null ? "" : value.toString(); }
}