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@michielmulders
Created March 30, 2018 11:22
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My First Solidity ERC20 ERC223 Token
pragma solidity ^0.4.0;
interface ERC20 {
function transferFrom(address _from, address _to, uint _value) public returns (bool);
function approve(address _spender, uint _value) public returns (bool);
function allowance(address _owner, address _spender) public constant returns (uint);
event Approval(address indexed _owner, address indexed _spender, uint _value);
}
interface ERC223 {
function transfer(address _to, uint _value, bytes _data) public returns (bool);
event Transfer(address indexed from, address indexed to, uint value, bytes indexed data);
}
contract ERC223ReceivingContract {
function tokenFallback(address _from, uint _value, bytes _data) public;
}
contract Token {
string internal _symbol;
string internal _name;
uint8 internal _decimals;
uint internal _totalSupply = 1000;
mapping (address => uint) internal _balanceOf;
mapping (address => mapping (address => uint)) internal _allowances;
function Token(string symbol, string name, uint8 decimals, uint totalSupply) public {
_symbol = symbol;
_name = name;
_decimals = decimals;
_totalSupply = totalSupply;
}
function name() public constant returns (string) {
return _name;
}
function symbol() public constant returns (string) {
return _symbol;
}
function decimals() public constant returns (uint8) {
return _decimals;
}
function totalSupply() public constant returns (uint) {
return _totalSupply;
}
function balanceOf(address _addr) public constant returns (uint);
function transfer(address _to, uint _value) public returns (bool);
event Transfer(address indexed _from, address indexed _to, uint _value);
}
library SafeMath {
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a * b;
assert(a == 0 || c / a == b);
return c;
}
function div(uint256 a, uint256 b) internal pure returns (uint256) {
// assert(b > 0); // Solidity automatically throws when dividing by 0
uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
assert(b <= a);
return a - b;
}
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
assert(c >= a);
return c;
}
}
contract MyFirstToken is Token("MFT", "My First Token", 18, 1000), ERC20, ERC223 {
using SafeMath for uint;
function MyFirstToken() public {
_balanceOf[msg.sender] = _totalSupply;
}
function totalSupply() public constant returns (uint) {
return _totalSupply;
}
function balanceOf(address _addr) public constant returns (uint) {
return _balanceOf[_addr];
}
function transfer(address _to, uint _value) public returns (bool) {
if (_value > 0 &&
_value <= _balanceOf[msg.sender] &&
!isContract(_to)) {
_balanceOf[msg.sender] = _balanceOf[msg.sender].sub(_value);
_balanceOf[_to] = _balanceOf[_to].add(_value);
emit Transfer(msg.sender, _to, _value);
return true;
}
return false;
}
function transfer(address _to, uint _value, bytes _data) public returns (bool) {
if (_value > 0 &&
_value <= _balanceOf[msg.sender] &&
isContract(_to)) {
_balanceOf[msg.sender] = _balanceOf[msg.sender].sub(_value);
_balanceOf[_to] = _balanceOf[_to].add(_value);
ERC223ReceivingContract _contract = ERC223ReceivingContract(_to);
_contract.tokenFallback(msg.sender, _value, _data);
emit Transfer(msg.sender, _to, _value, _data);
return true;
}
return false;
}
function isContract(address _addr) private constant returns (bool) {
uint codeSize;
assembly {
codeSize := extcodesize(_addr)
}
return codeSize > 0;
}
function transferFrom(address _from, address _to, uint _value) public returns (bool) {
if (_allowances[_from][msg.sender] > 0 &&
_value > 0 &&
_allowances[_from][msg.sender] >= _value &&
_balanceOf[_from] >= _value) {
_balanceOf[_from] = _balanceOf[_from].sub(_value);
_balanceOf[_to] = _balanceOf[_to].add(_value);
_allowances[_from][msg.sender] = _allowances[_from][msg.sender].sub(_value);
emit Transfer(_from, _to, _value);
return true;
}
return false;
}
function approve(address _spender, uint _value) public returns (bool) {
_allowances[msg.sender][_spender] = _allowances[msg.sender][_spender].add(_value);
emit Approval(msg.sender, _spender, _value);
return true;
}
function allowance(address _owner, address _spender) public constant returns (uint) {
return _allowances[_owner][_spender];
}
}
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