persistable sclass G22NetworkElement > MetaWithChangeListeners {
  // network element belongs to
  settable G22Network network;
  
  // position in visual representation
  settable Rect bounds;
  
  // identifier in network (optional)
  settable S identifier;
  
  // script code to adapt element and to create instance
  settableWithVar S code;
  
  {
    onChange(-> network?.change());
  }
  
  class Port {
    // position on element's border (0 to 1, 0 to 1)
    settable DoubleRect position;
    
    // name of port
    settable S name;
    
    // cable attached to this port
    settable G22NetworkCable cable;
  }
  
  L<Port> ports = syncL();
  
  LASCompileResult newCompileResult() { ret new LASCompileResult; }
  
  transient LASCompileResult compileResult;
  LASCompileResult compile(G22Utils g22utils) {
    S code = this.code;
    if (code == null) null;
    var cr = compileResult;
    if (cr != null && eq(cr.script, code)) ret cr;
    cr = newCompileResult();
    cr.script(code).parser(g22utils.leftArrowParser()).compile();
    ret compileResult = cr;
  }
  
  // TODO
  O makeInstance() { null; }
  
  toString { ret or2(identifier(), "Unnamed element"); }
}