if (name instanceof CallbackFunction) return ((CallbackFunction) name).getFunction();  AbstractFunction fun = findFunction(name.toString());
if (fun != null) return fun;  fun = findFunction(name);
  public AbstractFunction getFunction(Value name)  {    name = name.toValue();    if (name instanceof CallbackFunction)      return ((CallbackFunction) name).getFunction();    AbstractFunction fun = findFunction(name.toString());    if (fun != null)      return fun;    throw errorException(L.l("'{0}' is an unknown function.", name));  }