docs: @Override
    public <VALUEBASE, VALUE extends VALUEBASE, KEY extends Key<CoreMap, VALUEBASE>>
      VALUE set(Class<KEY> key, VALUE value) {
      
      if (immutableKeys.contains(key)) {
        throw new HashableCoreMapException("Attempt to change value " +
        		"of immutable field "+key.getSimpleName());
      }
      
      return super.set(key, value);
    }