Why can't I update this mapping in my burn function?

Question

I am trying to update a mapping of the owner's token count when the owner burns a token.

mapping (address => uint) public ownerTokenCount; //# of tokens in wallet

It gets updated here:

_mintToken(owner) {

userTokenCount(owner) = userTokenCount(owner) + 1

_mint;

}

It should update again here but it is not.

_burntoken(owner){

(require userTokenCount(owner) >0); // this throws

userTokenCount(owner) = userTokenCount(owner) - 1;

_burn;

}

Answer 1

To access a map you need to use []

For example:

function _burntoken(address owner) private {

    require (userTokenCount[owner] > 0);

    userTokenCount[owner] = userTokenCount[owner] - 1;

    _burn();

}