Class TQuBit for Harbour:
https://github.com/FiveTechSoft/quantum-computing-with-Harbour
For those that want to think about the next step:
https://elpais.com/ciencia/cafe-y-teoremas/2021-12-02/la-teoria-cuantica-es-mas-coherente-de-lo-que-creiamos.html?outputType=amp