[Connect C++] How to check if level code is valid in level library?

I have old code like below to check if level code is valid before using it. As LEVEL_LIBRARY_MODELREF is goner, how should this be handled with Connect?

 if (mdlLevel_isValidByCode(ACTIVEMODEL, value) || 
     mdlLevel_isValidByCode(LEVEL_LIBRARY_MODELREF, value))
  mdlLevel_setActiveByCode(value);