Files
openzeppelin-contracts/contracts/token/ERC20/BurnableToken.sol
John Shutt ad12381549 update constructor syntax for solidity 0.4.23 in numerous contracts (#921)
* update solidity-coverage to ^0.5.0

* update truffle dependency to ^4.1.8

* update solium to ^1.1.7

* update all contracts to solidity ^0.4.23
2018-05-08 18:02:00 -07:00

33 lines
871 B
Solidity

pragma solidity ^0.4.23;
import "./BasicToken.sol";
/**
* @title Burnable Token
* @dev Token that can be irreversibly burned (destroyed).
*/
contract BurnableToken is BasicToken {
event Burn(address indexed burner, uint256 value);
/**
* @dev Burns a specific amount of tokens.
* @param _value The amount of token to be burned.
*/
function burn(uint256 _value) public {
_burn(msg.sender, _value);
}
function _burn(address _who, uint256 _value) internal {
require(_value <= balances[_who]);
// no need to require value <= totalSupply, since that would imply the
// sender's balance is greater than the totalSupply, which *should* be an assertion failure
balances[_who] = balances[_who].sub(_value);
totalSupply_ = totalSupply_.sub(_value);
emit Burn(_who, _value);
emit Transfer(_who, address(0), _value);
}
}