// returns true if change
sbool cSmartSetField_withConverter(Concept c, S field, O value, ValueConverterForField converter) ctex {
  Field f = setOpt_findField(c.getClass(), field);
  
  if (f != null) {
    if (converter != null && value != null) {
      OrError<O> result = converter.convertValue(c, f, value);
      if (result == null) fail("Unknown conversion " + className(value) + " => " + f);
      if (!result.ok()) fail("Unknown conversion " + className(value) + " => " + f + ": " + result.error());
      value = result!;
    }
    
    // convert L to RefL
    if (value instanceof L && f.getType() == Concept.RefL.class) {
      ((Concept.RefL) f.get(c)).replaceWithList((L) value);
      true;
    }
    
    // convert concept to Ref
    
    if (value instanceof Concept && f.getType() == Concept.Ref.class)
      ret ((Concept.Ref) f.get(c)).set((Concept) value);
  }
 
  ret _csetField(c, field, value);
}