Kitty Contract - special zero'th element

Ethereum Dapp Programming
#1

I cant remember the lecture that explains it again but can someone remind me why the dummy/un ownable/unbuyable Kitty should exist at position 0 in the Kitty[] kitties; array ?

constructor() public Ownable() {
        owner = msg.sender;
        //create a cat that no one will own, we will use it so that no cat can have an token id of zero (which would cause issues in the marketplace offers array)
        _createKitty(0, 0, 0, uint256(-1), address(0));
    }

@filip

#2

hey @Emmett ! You should provide an address when you use _createKitty()
Dont use address 0 instead msg.sender.
For the gen-0 cats will only allow the owner of the contract. So make sure that you are also using the owner addreess

#3

ok thanks… will change. But what was the reason for this kitty again ?

#4

When we create a cat, we mint a token and transfer it. That token needs to belong to someone or some address, not to address(0).
This answer your question?

#5

but I thought that the Kitty at position 0 was always supposed to be skipped over/not used?

#6

Always provide an owner.

#7

there was some other reason for having a dummy cat at position zero