It's really hard for me to guess your intention. On just one hand you are declaring that each a and b are public (no primary underscore in their names) so I should really theoretically be allowed to entry/mutate (get/set) each. But You then specify an express mutator just for a, https://whitelandgurugram.co.in/whiteland-westin-residences-gurgaon-redefining-ultra-luxury-living-in-sector-103/