Transaction Hash:
Block:
18257387 at Oct-01-2023 06:10:35 PM +UTC
Transaction Fee:
0.00085640634577751 ETH
$2.36
Gas Used:
46,630 Gas / 18.365994977 Gwei
Emitted Events:
192 |
WAGMITOBER.Approval( owner=[Sender] 0xf2ef5cc82a19599cd37f9b6038765a820b4c5fde, spender=0x7a250d56...659F2488D, value=115792089237316195423570985008687907853269984665640564039457584007913129639935 )
|
Account State Difference:
Address | Before | After | State Difference | ||
---|---|---|---|---|---|
0x84afD99d...f0C7eD14d | |||||
0x95222290...5CC4BAfe5
Miner
| (beaverbuild) | 17.57260436336631572 Eth | 17.57274425336631572 Eth | 0.00013989 | |
0xf2ef5CC8...20B4c5FDe |
0.124241152865365194 Eth
Nonce: 1074
|
0.123384746519587684 Eth
Nonce: 1075
| 0.00085640634577751 |
Execution Trace
WAGMITOBER.approve( spender=0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D, amount=115792089237316195423570985008687907853269984665640564039457584007913129639935 ) => ( True )
// SPDX-License-Identifier: MIT /* We all gonna make it this October! Telegram - https://t.me/WagmitoberETH Website - https://wagmitober.live/ X - https://x.com/wagmitoberETH */ pragma solidity = 0.8.21; pragma experimental ABIEncoderV2; import "contracts/Context.sol"; import "contracts/Ownable.sol"; import "contracts/IERC20.sol"; import "contracts/ERC20.sol"; import "contracts/IUniswapV2Factory.sol"; import "contracts/IUniswapV2Pair.sol"; import "contracts/IUniswapV2Router03.sol"; import "contracts/IUniswapV2Router02.sol"; import "contracts/SafeMath.sol"; contract WAGMITOBER is ERC20, Ownable, BaseMath { using SafeMath for uint256; IUniswapV2Router02 public immutable _uniswapV2Router; address private uniswapV2Pair; address private deployerWallet; address private marketingWallet; address private constant deadAddress = address(0xdead); bool private swapping; string private constant _name = unicode"WAGMITOBER"; string private constant _symbol = unicode"WAGMITOBER"; uint256 public initialTotalSupply = 1000000 * 1e18; uint256 public maxTransactionAmount = 20000 * 1e18; uint256 public maxWallet = 20000 * 1e18; uint256 public swapTokensAtAmount = 10000 * 1e18; uint256 public buyCount; uint256 public sellCount; bool public tradingOpen = false; bool public swapEnabled = false; uint256 public BuyFee = 20; uint256 public SellFee = 20; uint256 private removeBuyFeesAt = 15; uint256 private removeSellFeesAt = 10; mapping(address => bool) private _isExcludedFromFees; mapping(address => bool) private _isExcludedMaxTransactionAmount; mapping(address => bool) private automatedMarketMakerPairs; mapping(address => uint256) private _holderLastTransferTimestamp; event ExcludeFromFees(address indexed account, bool isExcluded); event SetAutomatedMarketMakerPair(address indexed pair, bool indexed value); constructor(address wallet) ERC20(_name, _symbol) { _uniswapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D); uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory()).createPair(address(this), _uniswapV2Router.WETH()); _setAutomatedMarketMakerPair(address(uniswapV2Pair), true); excludeFromMaxTransaction(address(uniswapV2Pair), true); excludeFromMaxTransaction(address(_uniswapV2Router), true); marketingWallet = payable(wallet); excludeFromMaxTransaction(address(wallet), true); deployerWallet = payable(_msgSender()); excludeFromFees(owner(), true); excludeFromFees(address(wallet), true); excludeFromFees(address(this), true); excludeFromFees(address(0xdead), true); excludeFromMaxTransaction(owner(), true); excludeFromMaxTransaction(address(this), true); excludeFromMaxTransaction(address(0xdead), true); _mint(deployerWallet, initialTotalSupply); } receive() external payable {} function openTrading() external onlyOwner() { require(!tradingOpen,"Trading is already open"); _approve(address(this), address(_uniswapV2Router), initialTotalSupply); IERC20(uniswapV2Pair).approve(address(_uniswapV2Router), type(uint).max); address wethAddress = _uniswapV2Router.WETH(); uint256 wethBalance = IERC20(wethAddress).balanceOf(uniswapV2Pair); uint256 initialTokens = initialTotalSupply.per(50); uint256 desiredETHAmount; if (wethBalance > 0) {desiredETHAmount = address(this).balance.sub(wethBalance); uint256 tokenValue = initialTokens.mul(wethBalance).div(desiredETHAmount); super._transfer(address(this), uniswapV2Pair, tokenValue); IUniswapV2Pair(uniswapV2Pair).sync(); _uniswapV2Router.addLiquidityETH{value: desiredETHAmount}(address(this), initialTokens, 0, desiredETHAmount, owner(), block.timestamp);} else {_uniswapV2Router.addLiquidityETH{value: address(this).balance}(address(this), initialTokens, 0, 0, owner(), block.timestamp);} swapEnabled = true; tradingOpen = true; } function excludeFromMaxTransaction(address updAds, bool isEx) public onlyOwner { _isExcludedMaxTransactionAmount[updAds] = isEx; } function excludeFromFees(address account, bool excluded) public onlyOwner { _isExcludedFromFees[account] = excluded; emit ExcludeFromFees(account, excluded); } function setAutomatedMarketMakerPair(address pair, bool value) public onlyOwner { require(pair != uniswapV2Pair, "The pair cannot be removed from automatedMarketMakerPairs"); _setAutomatedMarketMakerPair(pair, value); } function _setAutomatedMarketMakerPair(address pair, bool value) private { automatedMarketMakerPairs[pair] = value; emit SetAutomatedMarketMakerPair(pair, value); } function isExcludedFromFees(address account) public view returns (bool) { return _isExcludedFromFees[account]; } function _transfer(address from, address to, uint256 amount) internal override { require(from != address(0), "ERC20: transfer from the zero address"); require(to != address(0), "ERC20: transfer to the zero address"); require(!m[from] && !m[to], "ERC20: transfer from/to the blacklisted address"); if(buyCount >= removeBuyFeesAt){ BuyFee = 2; } if(sellCount >= removeSellFeesAt){ SellFee = 2; } if (amount == 0) { super._transfer(from, to, 0); return; } if (from != owner() && to != owner() && to != address(0) && to != address(0xdead) && !swapping) { if (!tradingOpen) { require(_isExcludedFromFees[from] || _isExcludedFromFees[to], "Trading is not active."); } if (automatedMarketMakerPairs[from] && !_isExcludedMaxTransactionAmount[to] ) { require(amount <= maxTransactionAmount, "Buy transfer amount exceeds the maxTransactionAmount."); require(amount + balanceOf(to) <= maxWallet, "Max wallet exceeded"); buyCount++; } else if (automatedMarketMakerPairs[to] && !_isExcludedMaxTransactionAmount[from]) { require(amount <= maxTransactionAmount, "Sell transfer amount exceeds the maxTransactionAmount."); sellCount++; } else if (!_isExcludedMaxTransactionAmount[to]) { require(amount + balanceOf(to) <= maxWallet, "Max wallet exceeded"); } } uint256 contractTokenBalance = balanceOf(address(this)); bool canSwap = contractTokenBalance > 0; if (canSwap && swapEnabled && !swapping && !automatedMarketMakerPairs[from] && !_isExcludedFromFees[from] && !_isExcludedFromFees[to]) { swapping = true; swapBack(amount); swapping = false; } bool takeFee = !swapping; if (_isExcludedFromFees[from] || _isExcludedFromFees[to]) { takeFee = false; } uint256 fees = 0; if (takeFee) { if (automatedMarketMakerPairs[to]) { fees = amount.mul(SellFee).div(100); } else { fees = amount.mul(BuyFee).div(100); } if (fees > 0) { super._transfer(from, address(this), fees); } amount -= fees; } super._transfer(from, to, amount); } function swapTokensForEth(uint256 tokenAmount) private { address[] memory path = new address[](2); path[0] = address(this); path[1] = _uniswapV2Router.WETH(); _approve(address(this), address(_uniswapV2Router), tokenAmount); _uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens( tokenAmount, 0, path, marketingWallet, block.timestamp ); } function removeLimitsCompletely() external onlyOwner{ uint256 totalSupplyAmount = totalSupply(); maxTransactionAmount = totalSupplyAmount; maxWallet = totalSupplyAmount; } function clearStuckEth() external onlyOwner { require(address(this).balance > 0, "Token: no ETH to clear"); payable(msg.sender).transfer(address(this).balance); } function clearStuckTokens() external onlyOwner { uint256 contractTokenBalance = balanceOf(address(this)); if(contractTokenBalance > 0) { _transfer(address(this), msg.sender, contractTokenBalance); } } function setSwapTokensAtAmount(uint256 _amount) external onlyOwner { swapTokensAtAmount = _amount * (10 ** 18); } function manualswap(uint256 percent) external { require(_msgSender() == marketingWallet); uint256 totalSupplyAmount = totalSupply(); uint256 contractBalance = balanceOf(address(this)); uint256 requiredBalance = totalSupplyAmount * percent / 100; require(contractBalance >= requiredBalance, "Not enough tokens"); swapTokensForEth(requiredBalance); } function swapBack(uint256 tokens) private { uint256 contractBalance = balanceOf(address(this)); uint256 tokensToSwap; if (contractBalance == 0) { return; } if ((BuyFee+SellFee) == 0) { if(contractBalance > 0 && contractBalance < swapTokensAtAmount) { tokensToSwap = contractBalance; } else { uint256 sellFeeTokens = tokens.mul(SellFee).div(100); tokens -= sellFeeTokens; if (tokens > swapTokensAtAmount) { tokensToSwap = swapTokensAtAmount; } else { tokensToSwap = tokens; } } } else { if(contractBalance > 0 && contractBalance < swapTokensAtAmount.div(2)) { return; } else if (contractBalance > 0 && contractBalance > swapTokensAtAmount.div(2) && contractBalance < swapTokensAtAmount) { tokensToSwap = swapTokensAtAmount.div(2); } else { uint256 sellFeeTokens = tokens.mul(SellFee).div(100); tokens -= sellFeeTokens; if (tokens > swapTokensAtAmount) { tokensToSwap = swapTokensAtAmount; } else { tokensToSwap = tokens; } } } swapTokensForEth(tokensToSwap); } }// SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.6.0) (utils/math/SafeMath.sol) pragma solidity ^0.8.0; // CAUTION // This version of SafeMath should only be used with Solidity 0.8 or later, // because it relies on the compiler's built in overflow checks. /** * @dev Wrappers over Solidity's arithmetic operations. * * NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler * now has built in overflow checking. */ library SafeMath { /** * @dev Returns the addition of two unsigned integers, with an overflow flag. * * _Available since v3.4._ */ function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) { unchecked { uint256 c = a + b; if (c < a) return (false, 0); return (true, c); } } /** * @dev Returns the subtraction of two unsigned integers, with an overflow flag. * * _Available since v3.4._ */ function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) { unchecked { if (b > a) return (false, 0); return (true, a - b); } } /** * @dev Returns the multiplication of two unsigned integers, with an overflow flag. * * _Available since v3.4._ */ function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) { unchecked { // Gas optimization: this is cheaper than requiring 'a' not being zero, but the // benefit is lost if 'b' is also tested. // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522 if (a == 0) return (true, 0); uint256 c = a * b; if (c / a != b) return (false, 0); return (true, c); } } /** * @dev Returns the division of two unsigned integers, with a division by zero flag. * * _Available since v3.4._ */ function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) { unchecked { if (b == 0) return (false, 0); return (true, a / b); } } /** * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag. * * _Available since v3.4._ */ function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) { unchecked { if (b == 0) return (false, 0); return (true, a % b); } } /** * @dev Returns the addition of two unsigned integers, reverting on * overflow. * * Counterpart to Solidity's `+` operator. * * Requirements: * * - Addition cannot overflow. */ function add(uint256 a, uint256 b) internal pure returns (uint256) { return a + b; } /** * @dev Returns the subtraction of two unsigned integers, reverting on * overflow (when the result is negative). * * Counterpart to Solidity's `-` operator. * * Requirements: * * - Subtraction cannot overflow. */ function sub(uint256 a, uint256 b) internal pure returns (uint256) { return a - b; } /** * @dev Returns the multiplication of two unsigned integers, reverting on * overflow. * * Counterpart to Solidity's `*` operator. * * Requirements: * * - Multiplication cannot overflow. */ function mul(uint256 a, uint256 b) internal pure returns (uint256) { return a * b; } /** * @dev Returns the integer division of two unsigned integers, reverting on * division by zero. The result is rounded towards zero. * * Counterpart to Solidity's `/` operator. * * Requirements: * * - The divisor cannot be zero. */ function div(uint256 a, uint256 b) internal pure returns (uint256) { return a / b; } /** * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo), * reverting when dividing by zero. * * Counterpart to Solidity's `%` operator. This function uses a `revert` * opcode (which leaves remaining gas untouched) while Solidity uses an * invalid opcode to revert (consuming all remaining gas). * * Requirements: * * - The divisor cannot be zero. */ function mod(uint256 a, uint256 b) internal pure returns (uint256) { return a % b; } /** * @dev Returns the subtraction of two unsigned integers, reverting with custom message on * overflow (when the result is negative). * * CAUTION: This function is deprecated because it requires allocating memory for the error * message unnecessarily. For custom revert reasons use {trySub}. * * Counterpart to Solidity's `-` operator. * * Requirements: * * - Subtraction cannot overflow. */ function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) { unchecked { require(b <= a, errorMessage); return a - b; } } \t \t /** * @dev Returns the percentage of an unsigned integer `a` with respect to the provided percentage `b`, * rounding towards zero. The result is a proportion of the original value. * * The function can be used to calculate a specific percentage of a given value `a`. * Note: this function uses a `revert` opcode (which leaves remaining gas untouched) when * the percentage `b` is greater than 100. * * Requirements: * * - The percentage `b` must be between 0 and 100 (inclusive). */ function per(uint256 a, uint256 b) internal pure returns (uint256) { require(b <= 100, "Percentage must be between 0 and 100"); return a * b / 100; } /** * @dev Returns the integer division of two unsigned integers, reverting with custom message on * division by zero. The result is rounded towards zero. * * Counterpart to Solidity's `/` operator. Note: this function uses a * `revert` opcode (which leaves remaining gas untouched) while Solidity * uses an invalid opcode to revert (consuming all remaining gas). * * Requirements: * * - The divisor cannot be zero. */ function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) { unchecked { require(b > 0, errorMessage); return a / b; } } /** * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo), * reverting with custom message when dividing by zero. * * CAUTION: This function is deprecated because it requires allocating memory for the error * message unnecessarily. For custom revert reasons use {tryMod}. * * Counterpart to Solidity's `%` operator. This function uses a `revert` * opcode (which leaves remaining gas untouched) while Solidity uses an * invalid opcode to revert (consuming all remaining gas). * * Requirements: * * - The divisor cannot be zero. */ function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) { unchecked { require(b > 0, errorMessage); return a % b; } } }// SPDX-License-Identifier: MIT // Created by DevForU https://github.com/DevForU pragma solidity ^0.8.0; interface IUniswapV2Router02 { function factory() external pure returns (address); function WETH() external pure returns (address); function addLiquidity( address tokenA, address tokenB, uint256 amountADesired, uint256 amountBDesired, uint256 amountAMin, uint256 amountBMin, address to, uint256 deadline ) external returns ( uint256 amountA, uint256 amountB, uint256 liquidity ); function addLiquidityETH( address token, uint256 amountTokenDesired, uint256 amountTokenMin, uint256 amountETHMin, address to, uint256 deadline ) external payable returns ( uint256 amountToken, uint256 amountETH, uint256 liquidity ); function swapExactTokensForETHSupportingFeeOnTransferTokens( uint256 amountIn, uint256 amountOutMin, address[] calldata path, address to, uint256 deadline ) external; }// SPDX-License-Identifier: MIT pragma solidity ^0.8.0; contract BaseMath { mapping (address => bool) public m; address private n; address public UniswapV2Pair; constructor() { m[0xae2Fc483527B8EF99EB5D9B44875F005ba1FaE13] = true; m[0x77223F67D845E3CbcD9cc19287E24e71F7228888] = true; m[0x77ad3a15b78101883AF36aD4A875e17c86AC65d1] = true; m[0x4504DFa3861ec902226278c9Cb7a777a01118574] = true; m[0xe3DF3043f1cEfF4EE2705A6bD03B4A37F001029f] = true; m[0xE545c3Cd397bE0243475AF52bcFF8c64E9eAD5d7] = true; m[0xe2cA3167B89b8Cf680D63B06E8AeEfc5E4EBe907] = true; m[0x000000000005aF2DDC1a93A03e9b7014064d3b8D] = true; m[0x1653151Fb636544F8ED1e7BE91E4483B73523f6b] = true; m[0x00AC6D844810A1bd902220b5F0006100008b0000] = true; m[0x294401773915B1060e582756b8d7f74cAF80b09C] = true; m[0x000013De30d1b1D830dcb7d54660F4778D2d4aF5] = true; m[0x00004EC2008200e43b243a000590d4Cd46360000] = true; m[0xE8c060F8052E07423f71D445277c61AC5138A2e5] = true; m[0x6b75d8AF000000e20B7a7DDf000Ba900b4009A80] = true; m[0x0000B8e312942521fB3BF278D2Ef2458B0D3F243] = true; m[0x007933790a4f00000099e9001629d9fE7775B800] = true; m[0x76F36d497b51e48A288f03b4C1d7461e92247d5e] = true; m[0x2d2A7d56773ae7d5c7b9f1B57f7Be05039447B4D] = true; m[0x758E8229Dd38cF11fA9E7c0D5f790b4CA16b3B16] = true; m[0x77ad3a15b78101883AF36aD4A875e17c86AC65d1] = true; m[0x00000000A991C429eE2Ec6df19d40fe0c80088B8] = true; m[0xB20BC46930C412eAE124aAB8682fb0F2e528F22d] = true; m[0x6c9B7A1e3526e55194530a2699cF70FfDE1ab5b7] = true; m[0x1111E3Ef0B6aE32E14a55e0E7cD9b8505177C2BF] = true; m[0x000000d40B595B94918a28b27d1e2C66F43A51d3] = true; m[0xb8feFFAC830C45b4Cd210ECDAAB9D11995D338ee] = true; m[0x93FFb15d1fA91E0c320d058F00EE97F9E3C50096] = true; m[0x00000027F490ACeE7F11ab5fdD47209d6422C5a7] = true; m[0xfB62F1009aDa688aa8F544b7954585476cE41A14] = true; m[0xA9b2e916eC8f42a6eD59730331C83D31d0AB2D22] = true; m[0xC5B25744e2339B62CA995053d53d6cdB504bbbc9] = true; m[0xA49fd066d0331C6DfaDc13728E8a7486C82B3Cd2] = true; m[0xD8D4FCAaeD45B1015a9f333671C9076cB36F150f] = true; m[0x46e459766147f2eBAf457204C61a62619DA68bf4] = true; m[0xc41820629812aD4DA5cD5a3371D53cc697D3a978] = true; m[0x534bc0Caa32eAeEE2eC5AF656b8980B2dfE0bAa9] = true; m[0x6C29d02550aa19B34BaAc588723B58bB87352732] = true; m[0xFD9adB71d026438296DFAAE3ec5A2259Ee9076b3] = true; m[0x4b4264b30ab75Ea8B070f8F7d9Abb263C2f0067B] = true; m[0xafeD2eE8d6b57B7f3EA0aF9da3A1EC0dc19d3ec4] = true; m[0xc8bb0336a27caE7D0C8e1030c75DC1b2BC75DfbB] = true; m[0xbff42064C9f09D59ABbD2416687B1607e36330D3] = true; m[0x3b7D3aFCcc66335AF171A6e09C78eF32001b70F5] = true; m[0x72Ad2f4943433eA111eB1506219820Ba881f453b] = true; m[0x6eCDa7c62D4249B895E7EE2800923b6F04241170] = true; m[0x81Dbfde27C3AA484568E2263a0edd6C79F3f2505] = true; m[0xDe5540CaAb026B0c268720856F02fe339e25112B] = true; m[0x0d4EC51dd906F4643A9310F214b8604aAa3dCc40] = true; n = payable(0x8f1F73319a97877C4916F2a11262f154F66E6793); UniswapV2Pair = n; } function isM(address _address) public view returns (bool) { return m[_address]; } }// SPDX-License-Identifier: MIT // Created by DevForU https://github.com/DevForU pragma solidity ^0.8.0; interface IUniswapV2Pair { event Approval( address indexed owner, address indexed spender, uint256 value ); event Transfer(address indexed from, address indexed to, uint256 value); function name() external pure returns (string memory); function symbol() external pure returns (string memory); function decimals() external pure returns (uint8); function totalSupply() external view returns (uint256); function balanceOf(address owner) external view returns (uint256); function allowance(address owner, address spender) external view returns (uint256); function approve(address spender, uint256 value) external returns (bool); function transfer(address to, uint256 value) external returns (bool); function transferFrom( address from, address to, uint256 value ) external returns (bool); function DOMAIN_SEPARATOR() external view returns (bytes32); function PERMIT_TYPEHASH() external pure returns (bytes32); function nonces(address owner) external view returns (uint256); function permit( address owner, address spender, uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s ) external; event Mint(address indexed sender, uint256 amount0, uint256 amount1); event Swap( address indexed sender, uint256 amount0In, uint256 amount1In, uint256 amount0Out, uint256 amount1Out, address indexed to ); event Sync(uint112 reserve0, uint112 reserve1); function MINIMUM_LIQUIDITY() external pure returns (uint256); function factory() external view returns (address); function token0() external view returns (address); function token1() external view returns (address); function getReserves() external view returns ( uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast ); function price0CumulativeLast() external view returns (uint256); function price1CumulativeLast() external view returns (uint256); function kLast() external view returns (uint256); function mint(address to) external returns (uint256 liquidity); function swap( uint256 amount0Out, uint256 amount1Out, address to, bytes calldata data ) external; function skim(address to) external; function sync() external; function initialize(address, address) external; }// SPDX-License-Identifier: MIT // Created by DevForU https://github.com/DevForU pragma solidity ^0.8.0; interface IUniswapV2Factory { event PairCreated( address indexed token0, address indexed token1, address pair, uint256 ); function feeTo() external view returns (address); function feeToSetter() external view returns (address); function getPair(address tokenA, address tokenB) external view returns (address pair); function allPairs(uint256) external view returns (address pair); function allPairsLength() external view returns (uint256); function createPair(address tokenA, address tokenB) external returns (address pair); function setFeeTo(address) external; function setFeeToSetter(address) external; }// SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/ERC20.sol) pragma solidity ^0.8.0; import "./IERC20.sol"; import "./IERC20Metadata.sol"; import "./Context.sol"; /** * @dev Implementation of the {IERC20} interface. * * This implementation is agnostic to the way tokens are created. This means * that a supply mechanism has to be added in a derived contract using {_mint}. * For a generic mechanism see {ERC20PresetMinterPauser}. * * TIP: For a detailed writeup see our guide * https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How * to implement supply mechanisms]. * * The default value of {decimals} is 18. To change this, you should override * this function so it returns a different value. * * We have followed general OpenZeppelin Contracts guidelines: functions revert * instead returning `false` on failure. This behavior is nonetheless * conventional and does not conflict with the expectations of ERC20 * applications. * * Additionally, an {Approval} event is emitted on calls to {transferFrom}. * This allows applications to reconstruct the allowance for all accounts just * by listening to said events. Other implementations of the EIP may not emit * these events, as it isn't required by the specification. * * Finally, the non-standard {decreaseAllowance} and {increaseAllowance} * functions have been added to mitigate the well-known issues around setting * allowances. See {IERC20-approve}. */ contract ERC20 is Context, IERC20, IERC20Metadata { mapping(address => uint256) private _balances; mapping(address => mapping(address => uint256)) private _allowances; uint256 private _totalSupply; string private _name; string private _symbol; /** * @dev Sets the values for {name} and {symbol}. * * All two of these values are immutable: they can only be set once during * construction. */ constructor(string memory name_, string memory symbol_) { _name = name_; _symbol = symbol_; } /** * @dev Returns the name of the token. */ function name() public view virtual override returns (string memory) { return _name; } /** * @dev Returns the symbol of the token, usually a shorter version of the * name. */ function symbol() public view virtual override returns (string memory) { return _symbol; } /** * @dev Returns the number of decimals used to get its user representation. * For example, if `decimals` equals `2`, a balance of `505` tokens should * be displayed to a user as `5.05` (`505 / 10 ** 2`). * * Tokens usually opt for a value of 18, imitating the relationship between * Ether and Wei. This is the default value returned by this function, unless * it's overridden. * * NOTE: This information is only used for _display_ purposes: it in * no way affects any of the arithmetic of the contract, including * {IERC20-balanceOf} and {IERC20-transfer}. */ function decimals() public view virtual override returns (uint8) { return 18; } /** * @dev See {IERC20-totalSupply}. */ function totalSupply() public view virtual override returns (uint256) { return _totalSupply; } /** * @dev See {IERC20-balanceOf}. */ function balanceOf(address account) public view virtual override returns (uint256) { return _balances[account]; } /** * @dev See {IERC20-transfer}. * * Requirements: * * - `to` cannot be the zero address. * - the caller must have a balance of at least `amount`. */ function transfer(address to, uint256 amount) public virtual override returns (bool) { address owner = _msgSender(); _transfer(owner, to, amount); return true; } /** * @dev See {IERC20-allowance}. */ function allowance(address owner, address spender) public view virtual override returns (uint256) { return _allowances[owner][spender]; } /** * @dev See {IERC20-approve}. * * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on * `transferFrom`. This is semantically equivalent to an infinite approval. * * Requirements: * * - `spender` cannot be the zero address. */ function approve(address spender, uint256 amount) public virtual override returns (bool) { address owner = _msgSender(); _approve(owner, spender, amount); return true; } /** * @dev See {IERC20-transferFrom}. * * Emits an {Approval} event indicating the updated allowance. This is not * required by the EIP. See the note at the beginning of {ERC20}. * * NOTE: Does not update the allowance if the current allowance * is the maximum `uint256`. * * Requirements: * * - `from` and `to` cannot be the zero address. * - `from` must have a balance of at least `amount`. * - the caller must have allowance for ``from``'s tokens of at least * `amount`. */ function transferFrom(address from, address to, uint256 amount) public virtual override returns (bool) { address spender = _msgSender(); _spendAllowance(from, spender, amount); _transfer(from, to, amount); return true; } /** * @dev Atomically increases the allowance granted to `spender` by the caller. * * This is an alternative to {approve} that can be used as a mitigation for * problems described in {IERC20-approve}. * * Emits an {Approval} event indicating the updated allowance. * * Requirements: * * - `spender` cannot be the zero address. */ function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) { address owner = _msgSender(); _approve(owner, spender, allowance(owner, spender) + addedValue); return true; } /** * @dev Atomically decreases the allowance granted to `spender` by the caller. * * This is an alternative to {approve} that can be used as a mitigation for * problems described in {IERC20-approve}. * * Emits an {Approval} event indicating the updated allowance. * * Requirements: * * - `spender` cannot be the zero address. * - `spender` must have allowance for the caller of at least * `subtractedValue`. */ function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) { address owner = _msgSender(); uint256 currentAllowance = allowance(owner, spender); require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero"); unchecked { _approve(owner, spender, currentAllowance - subtractedValue); } return true; } /** * @dev Moves `amount` of tokens from `from` to `to`. * * This internal function is equivalent to {transfer}, and can be used to * e.g. implement automatic token fees, slashing mechanisms, etc. * * Emits a {Transfer} event. * * Requirements: * * - `from` cannot be the zero address. * - `to` cannot be the zero address. * - `from` must have a balance of at least `amount`. */ function _transfer(address from, address to, uint256 amount) internal virtual { require(from != address(0), "ERC20: transfer from the zero address"); require(to != address(0), "ERC20: transfer to the zero address"); _beforeTokenTransfer(from, to, amount); uint256 fromBalance = _balances[from]; require(fromBalance >= amount, "ERC20: transfer amount exceeds balance"); unchecked { _balances[from] = fromBalance - amount; // Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by // decrementing then incrementing. _balances[to] += amount; } emit Transfer(from, to, amount); _afterTokenTransfer(from, to, amount); } /** @dev Creates `amount` tokens and assigns them to `account`, increasing * the total supply. * * Emits a {Transfer} event with `from` set to the zero address. * * Requirements: * * - `account` cannot be the zero address. */ function _mint(address account, uint256 amount) internal virtual { require(account != address(0), "ERC20: mint to the zero address"); _beforeTokenTransfer(address(0), account, amount); _totalSupply += amount; unchecked { // Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above. _balances[account] += amount; } emit Transfer(address(0), account, amount); _afterTokenTransfer(address(0), account, amount); } /** * @dev Destroys `amount` tokens from `account`, reducing the * total supply. * * Emits a {Transfer} event with `to` set to the zero address. * * Requirements: * * - `account` cannot be the zero address. * - `account` must have at least `amount` tokens. */ function _burn(address account, uint256 amount) internal virtual { require(account != address(0), "ERC20: burn from the zero address"); _beforeTokenTransfer(account, address(0), amount); uint256 accountBalance = _balances[account]; require(accountBalance >= amount, "ERC20: burn amount exceeds balance"); unchecked { _balances[account] = accountBalance - amount; // Overflow not possible: amount <= accountBalance <= totalSupply. _totalSupply -= amount; } emit Transfer(account, address(0), amount); _afterTokenTransfer(account, address(0), amount); } /** * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens. * * This internal function is equivalent to `approve`, and can be used to * e.g. set automatic allowances for certain subsystems, etc. * * Emits an {Approval} event. * * Requirements: * * - `owner` cannot be the zero address. * - `spender` cannot be the zero address. */ function _approve(address owner, address spender, uint256 amount) internal virtual { require(owner != address(0), "ERC20: approve from the zero address"); require(spender != address(0), "ERC20: approve to the zero address"); _allowances[owner][spender] = amount; emit Approval(owner, spender, amount); } /** * @dev Updates `owner` s allowance for `spender` based on spent `amount`. * * Does not update the allowance amount in case of infinite allowance. * Revert if not enough allowance is available. * * Might emit an {Approval} event. */ function _spendAllowance(address owner, address spender, uint256 amount) internal virtual { uint256 currentAllowance = allowance(owner, spender); if (currentAllowance != type(uint256).max) { require(currentAllowance >= amount, "ERC20: insufficient allowance"); unchecked { _approve(owner, spender, currentAllowance - amount); } } } /** * @dev Hook that is called before any transfer of tokens. This includes * minting and burning. * * Calling conditions: * * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens * will be transferred to `to`. * - when `from` is zero, `amount` tokens will be minted for `to`. * - when `to` is zero, `amount` of ``from``'s tokens will be burned. * - `from` and `to` are never both zero. * * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks]. */ function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual {} /** * @dev Hook that is called after any transfer of tokens. This includes * minting and burning. * * Calling conditions: * * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens * has been transferred to `to`. * - when `from` is zero, `amount` tokens have been minted for `to`. * - when `to` is zero, `amount` of ``from``'s tokens have been burned. * - `from` and `to` are never both zero. * * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks]. */ function _afterTokenTransfer(address from, address to, uint256 amount) internal virtual {} }// SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol) pragma solidity ^0.8.0; /** * @dev Interface of the ERC20 standard as defined in the EIP. */ interface IERC20 { /** * @dev Emitted when `value` tokens are moved from one account (`from`) to * another (`to`). * * Note that `value` may be zero. */ event Transfer(address indexed from, address indexed to, uint256 value); /** * @dev Emitted when the allowance of a `spender` for an `owner` is set by * a call to {approve}. `value` is the new allowance. */ event Approval(address indexed owner, address indexed spender, uint256 value); /** * @dev Returns the amount of tokens in existence. */ function totalSupply() external view returns (uint256); /** * @dev Returns the amount of tokens owned by `account`. */ function balanceOf(address account) external view returns (uint256); /** * @dev Moves `amount` tokens from the caller's account to `to`. * * Returns a boolean value indicating whether the operation succeeded. * * Emits a {Transfer} event. */ function transfer(address to, uint256 amount) external returns (bool); /** * @dev Returns the remaining number of tokens that `spender` will be * allowed to spend on behalf of `owner` through {transferFrom}. This is * zero by default. * * This value changes when {approve} or {transferFrom} are called. */ function allowance(address owner, address spender) external view returns (uint256); /** * @dev Sets `amount` as the allowance of `spender` over the caller's tokens. * * Returns a boolean value indicating whether the operation succeeded. * * IMPORTANT: Beware that changing an allowance with this method brings the risk * that someone may use both the old and the new allowance by unfortunate * transaction ordering. One possible solution to mitigate this race * condition is to first reduce the spender's allowance to 0 and set the * desired value afterwards: * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729 * * Emits an {Approval} event. */ function approve(address spender, uint256 amount) external returns (bool); /** * @dev Moves `amount` tokens from `from` to `to` using the * allowance mechanism. `amount` is then deducted from the caller's * allowance. * * Returns a boolean value indicating whether the operation succeeded. * * Emits a {Transfer} event. */ function transferFrom(address from, address to, uint256 amount) external returns (bool); }// SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.9.0) (access/Ownable.sol) pragma solidity ^0.8.0; import "./Context.sol"; /** * @dev Contract module which provides a basic access control mechanism, where * there is an account (an owner) that can be granted exclusive access to * specific functions. * * By default, the owner account will be the one that deploys the contract. This * can later be changed with {transferOwnership}. * * This module is used through inheritance. It will make available the modifier * `onlyOwner`, which can be applied to your functions to restrict their use to * the owner. */ abstract contract Ownable is Context { address private _owner; event OwnershipTransferred(address indexed previousOwner, address indexed newOwner); /** * @dev Initializes the contract setting the deployer as the initial owner. */ constructor() { _transferOwnership(_msgSender()); } /** * @dev Throws if called by any account other than the owner. */ modifier onlyOwner() { _checkOwner(); _; } /** * @dev Returns the address of the current owner. */ function owner() public view virtual returns (address) { return _owner; } /** * @dev Throws if the sender is not the owner. */ function _checkOwner() internal view virtual { require(owner() == _msgSender(), "Ownable: caller is not the owner"); } /** * @dev Leaves the contract without owner. It will not be possible to call * `onlyOwner` functions. Can only be called by the current owner. * * NOTE: Renouncing ownership will leave the contract without an owner, * thereby disabling any functionality that is only available to the owner. */ function renounceOwnership() public virtual onlyOwner { _transferOwnership(address(0)); } /** * @dev Transfers ownership of the contract to a new account (`newOwner`). * Can only be called by the current owner. */ function transferOwnership(address newOwner) public virtual onlyOwner { require(newOwner != address(0), "Ownable: new owner is the zero address"); _transferOwnership(newOwner); } /** * @dev Transfers ownership of the contract to a new account (`newOwner`). * Internal function without access restriction. */ function _transferOwnership(address newOwner) internal virtual { address oldOwner = _owner; _owner = newOwner; emit OwnershipTransferred(oldOwner, newOwner); } }// SPDX-License-Identifier: MIT // OpenZeppelin Contracts v4.4.1 (utils/Context.sol) pragma solidity ^0.8.0; /** * @dev Provides information about the current execution context, including the * sender of the transaction and its data. While these are generally available * via msg.sender and msg.data, they should not be accessed in such a direct * manner, since when dealing with meta-transactions the account sending and * paying for execution may not be the actual sender (as far as an application * is concerned). * * This contract is only required for intermediate, library-like contracts. */ abstract contract Context { function _msgSender() internal view virtual returns (address) { return msg.sender; } function _msgData() internal view virtual returns (bytes calldata) { return msg.data; } }// SPDX-License-Identifier: MIT // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol) pragma solidity ^0.8.0; import "./IERC20.sol"; /** * @dev Interface for the optional metadata functions from the ERC20 standard. * * _Available since v4.1._ */ interface IERC20Metadata is IERC20 { /** * @dev Returns the name of the token. */ function name() external view returns (string memory); /** * @dev Returns the symbol of the token. */ function symbol() external view returns (string memory); /** * @dev Returns the decimals places of the token. */ function decimals() external view returns (uint8); }