creating Ethereum tokens as mining rewards - token

Question

I have managed to create a registered Ethereum "Token" using Primarily the "how to" from the Frontier website. I intend to proceed with a crowdsource ing contract to raise funds for what will be a fundraising event capable of doing some good in the world, but more on that later. The token creation text includes this suggestion for improving the functionality of my new token:
You could for example reward ethereum miners, by creating a transaction that will reward who found the current block:
mapping (uint => address) miningReward;
function claimMiningReward() {
if (miningReward[block.number] == 0) {
coinBalanceOf[block.coinbase] += 1;
miningReward[block.number] = block.coinbase;
}
}
simply pasting this code into my contract naturally produces error messages.
Q: What do I need to tweak, enter, change, to make it possible to reward minors with one of my tokens? for each and every mined new block.
Thank you.

Answer 1

You can copy and paste your code snippet into the token contract. It will look like that:
contract token {
mapping (address => uint) public coinBalanceOf;
event CoinTransfer(address sender, address receiver, uint amount);
/* Initializes contract with initial supply tokens to the creator of the contract */
function token(uint supply) {
if (supply == 0) supply = 10000;
coinBalanceOf[msg.sender] = supply;
}
/* Very simple trade function */
function sendCoin(address receiver, uint amount) returns(bool sufficient) {
if (coinBalanceOf[msg.sender] < amount) return false;
coinBalanceOf[msg.sender] -= amount;
coinBalanceOf[receiver] += amount;
CoinTransfer(msg.sender, receiver, amount);
return true;
}
mapping (uint => address) miningReward;
/* Reward Ethereum block miner with a token */
function claimMiningReward() {
if (miningReward[block.number] == 0) {
coinBalanceOf[block.coinbase] += 1;
miningReward[block.number] = block.coinbase;
}
}
}

Answer 2

I dont know if you figured this out yet. Anyone else having the same issue try the following snippet:
contract MyToken {
/* Public variables of the token */
string public name;
string public symbol;
uint8 public decimals;
/* This creates an array with all balances */
mapping (address => uint256) public balanceOf;
/* This generates a public event on the blockchain that will notify clients */
event Transfer(address indexed from, address indexed to, uint256 value);
/* Initializes contract with initial supply tokens to the creator of the contract */
function MyToken(uint256 _supply, string _name, string _symbol, uint8 _decimals) {
/* if supply not given then generate 1 million of the smallest unit of the token */
if (_supply == 0) _supply = 1000000;
/* Unless you add other functions these variables will never change */
balanceOf[msg.sender] = _supply;
name = _name;
symbol = _symbol;
/* If you want a divisible token then add the amount of decimals the base unit has */
decimals = _decimals;
}
/* Send coins */
function transfer(address _to, uint256 _value) {
/* if the sender doenst have enough balance then stop */
if (balanceOf[msg.sender] < _value) throw;
if (balanceOf[_to] + _value < balanceOf[_to]) throw;
/* Add and subtract new balances */
balanceOf[msg.sender] -= _value;
balanceOf[_to] += _value;
/* Notifiy anyone listening that this transfer took place */
Transfer(msg.sender, _to, _value);
}
}
Then adding your code to reward the miners but changing "coinBalanceOf" with "balanceOf" like so:
mapping (uint => address) miningReward;
function claimMiningReward() {
if (miningReward[block.number] == 0) {
balanceOf[block.coinbase] += 1;
miningReward[block.number] = block.coinbase;
}
}
So Your final contract would look like this:
contract MyToken {
/* Public variables of the token */
string public name;
string public symbol;
uint8 public decimals;
/* This creates an array with all balances */
mapping (address => uint256) public balanceOf;
/* This generates a public event on the blockchain that will notify clients */
event Transfer(address indexed from, address indexed to, uint256 value);
/* Initializes contract with initial supply tokens to the creator of the contract */
function MyToken(uint256 _supply, string _name, string _symbol, uint8 _decimals) {
/* if supply not given then generate 1 million of the smallest unit of the token */
if (_supply == 0) _supply = 1000000;
/* Unless you add other functions these variables will never change */
balanceOf[msg.sender] = _supply;
name = _name;
symbol = _symbol;
/* If you want a divisible token then add the amount of decimals the base unit has */
decimals = _decimals;
}
/* Send coins */
function transfer(address _to, uint256 _value) {
/* if the sender doenst have enough balance then stop */
if (balanceOf[msg.sender] < _value) throw;
if (balanceOf[_to] + _value < balanceOf[_to]) throw;
/* Add and subtract new balances */
balanceOf[msg.sender] -= _value;
balanceOf[_to] += _value;
/* Notifiy anyone listening that this transfer took place */
Transfer(msg.sender, _to, _value);
}
mapping (uint => address) miningReward;
function claimMiningReward() {
if (miningReward[block.number] == 0) {
balanceOf[block.coinbase] += 1;
miningReward[block.number] = block.coinbase;
}
}
}