✅Token Contract Verification
Compiler Version (solc):
v0.8.20+commit.a1b79de6Open Source License Type:
MITEVM Version:
parisOptimization:
trueOptimization Runs:
4294967295Constructor Arguments:
{token name}, {token symbol}, 0, 080F8b793FE69Fe9e65b5aE17b10F987c95530Bf)
{
"language": "Solidity",
"settings": {
"optimizer": { "enabled": true, "runs": 4294967295 },
"metadata": { "bytecodeHash": "none" },
"evmVersion": "paris",
"outputSelection": {
"*": {
"*": ["abi", "evm.bytecode", "evm.deployedBytecode", "evm.methodIdentifiers", "metadata"],
"": ["ast"]
}
}
},
"sources": {
"main.sol": {
"content": "// SPDX-License-Identifier: MIT\npragma solidity ^0.8.20;\n\n/**\n * @dev Provides information about the current execution context, including the\n * sender of the transaction and its data. While these are generally available\n * via msg.sender and msg.data, they should not be accessed in such a direct\n * manner, since when dealing with meta-transactions the account sending and\n * paying for execution may not be the actual sender (as far as an application\n * is concerned).\n *\n * This contract is only required for intermediate, library-like contracts.\n */\nabstract contract Context {\n function _msgSender() internal view virtual returns (address) {\n return msg.sender;\n }\n\n function _msgData() internal view virtual returns (bytes calldata) {\n return msg.data;\n }\n\n function _contextSuffixLength() internal view virtual returns (uint256) {\n return 0;\n }\n}\n\n/**\n * @dev Contract module which provides a basic access control mechanism, where\n * there is an account (an owner) that can be granted exclusive access to\n * specific functions.\n *\n * The initial owner is set to the address provided by the deployer. This can\n * later be changed with {transferOwnership}.\n *\n * This module is used through inheritance. It will make available the modifier\n * `onlyOwner`, which can be applied to your functions to restrict their use to\n * the owner.\n */\nabstract contract Ownable is Context {\n address private _owner;\n\n /**\n * @dev The caller account is not authorized to perform an operation.\n */\n error OwnableUnauthorizedAccount(address account);\n\n /**\n * @dev The owner is not a valid owner account. (eg. `address(0)`)\n */\n error OwnableInvalidOwner(address owner);\n\n event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);\n\n /**\n * @dev Initializes the contract setting the address provided by the deployer as the initial owner.\n */\n constructor(address initialOwner) {\n if (initialOwner == address(0)) {\n revert OwnableInvalidOwner(address(0));\n }\n _transferOwnership(initialOwner);\n }\n\n /**\n * @dev Throws if called by any account other than the owner.\n */\n modifier onlyOwner() {\n _checkOwner();\n _;\n }\n\n /**\n * @dev Returns the address of the current owner.\n */\n function owner() public view virtual returns (address) {\n return _owner;\n }\n\n /**\n * @dev Throws if the sender is not the owner.\n */\n function _checkOwner() internal view virtual {\n if (owner() != _msgSender()) {\n revert OwnableUnauthorizedAccount(_msgSender());\n }\n }\n\n /**\n * @dev Leaves the contract without owner. It will not be possible to call\n * `onlyOwner` functions. Can only be called by the current owner.\n *\n * NOTE: Renouncing ownership will leave the contract without an owner,\n * thereby disabling any functionality that is only available to the owner.\n */\n function renounceOwnership() public virtual onlyOwner {\n _transferOwnership(address(0));\n }\n\n /**\n * @dev Transfers ownership of the contract to a new account (`newOwner`).\n * Can only be called by the current owner.\n */\n function transferOwnership(address newOwner) public virtual onlyOwner {\n if (newOwner == address(0)) {\n revert OwnableInvalidOwner(address(0));\n }\n _transferOwnership(newOwner);\n }\n\n /**\n * @dev Transfers ownership of the contract to a new account (`newOwner`).\n * Internal function without access restriction.\n */\n function _transferOwnership(address newOwner) internal virtual {\n address oldOwner = _owner;\n _owner = newOwner;\n emit OwnershipTransferred(oldOwner, newOwner);\n }\n}\n\n/**\n * @dev Interface of the ERC20 standard as defined in the EIP.\n */\ninterface IERC20 {\n /**\n * @dev Emitted when `value` tokens are moved from one account (`from`) to\n * another (`to`).\n *\n * Note that `value` may be zero.\n */\n event Transfer(address indexed from, address indexed to, uint256 value);\n\n /**\n * @dev Emitted when the allowance of a `spender` for an `owner` is set by\n * a call to {approve}. `value` is the new allowance.\n */\n event Approval(address indexed owner, address indexed spender, uint256 value);\n\n /**\n * @dev Returns the value of tokens in existence.\n */\n function totalSupply() external view returns (uint256);\n\n /**\n * @dev Returns the value of tokens owned by `account`.\n */\n function balanceOf(address account) external view returns (uint256);\n\n /**\n * @dev Moves a `value` amount of tokens from the caller's account to `to`.\n *\n * Returns a boolean value indicating whether the operation succeeded.\n *\n * Emits a {Transfer} event.\n */\n function transfer(address to, uint256 value) external returns (bool);\n\n /**\n * @dev Returns the remaining number of tokens that `spender` will be\n * allowed to spend on behalf of `owner` through {transferFrom}. This is\n * zero by default.\n *\n * This value changes when {approve} or {transferFrom} are called.\n */\n function allowance(address owner, address spender) external view returns (uint256);\n\n /**\n * @dev Sets a `value` amount of tokens as the allowance of `spender` over the\n * caller's tokens.\n *\n * Returns a boolean value indicating whether the operation succeeded.\n *\n * IMPORTANT: Beware that changing an allowance with this method brings the risk\n * that someone may use both the old and the new allowance by unfortunate\n * transaction ordering. One possible solution to mitigate this race\n * condition is to first reduce the spender's allowance to 0 and set the\n * desired value afterwards:\n * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729\n *\n * Emits an {Approval} event.\n */\n function approve(address spender, uint256 value) external returns (bool);\n\n /**\n * @dev Moves a `value` amount of tokens from `from` to `to` using the\n * allowance mechanism. `value` is then deducted from the caller's\n * allowance.\n *\n * Returns a boolean value indicating whether the operation succeeded.\n *\n * Emits a {Transfer} event.\n */\n function transferFrom(address from, address to, uint256 value) external returns (bool);\n}\n\n/**\n * @dev Interface for the optional metadata functions from the ERC20 standard.\n */\ninterface IERC20Metadata is IERC20 {\n /**\n * @dev Returns the name of the token.\n */\n function name() external view returns (string memory);\n\n /**\n * @dev Returns the symbol of the token.\n */\n function symbol() external view returns (string memory);\n\n /**\n * @dev Returns the decimals places of the token.\n */\n function decimals() external view returns (uint8);\n}\n\n/**\n * @dev Standard ERC20 Errors\n * Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC20 tokens.\n */\ninterface IERC20Errors {\n /**\n * @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers.\n * @param sender Address whose tokens are being transferred.\n * @param balance Current balance for the interacting account.\n * @param needed Minimum amount required to perform a transfer.\n */\n error ERC20InsufficientBalance(address sender, uint256 balance, uint256 needed);\n\n /**\n * @dev Indicates a failure with the token `sender`. Used in transfers.\n * @param sender Address whose tokens are being transferred.\n */\n error ERC20InvalidSender(address sender);\n\n /**\n * @dev Indicates a failure with the token `receiver`. Used in transfers.\n * @param receiver Address to which tokens are being transferred.\n */\n error ERC20InvalidReceiver(address receiver);\n\n /**\n * @dev Indicates a failure with the `spender`’s `allowance`. Used in transfers.\n * @param spender Address that may be allowed to operate on tokens without being their owner.\n * @param allowance Amount of tokens a `spender` is allowed to operate with.\n * @param needed Minimum amount required to perform a transfer.\n */\n error ERC20InsufficientAllowance(address spender, uint256 allowance, uint256 needed);\n\n /**\n * @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.\n * @param approver Address initiating an approval operation.\n */\n error ERC20InvalidApprover(address approver);\n\n /**\n * @dev Indicates a failure with the `spender` to be approved. Used in approvals.\n * @param spender Address that may be allowed to operate on tokens without being their owner.\n */\n error ERC20InvalidSpender(address spender);\n}\n\n/**\n * @dev Standard ERC721 Errors\n * Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC721 tokens.\n */\ninterface IERC721Errors {\n /**\n * @dev Indicates that an address can't be an owner. For example, `address(0)` is a forbidden owner in EIP-20.\n * Used in balance queries.\n * @param owner Address of the current owner of a token.\n */\n error ERC721InvalidOwner(address owner);\n\n /**\n * @dev Indicates a `tokenId` whose `owner` is the zero address.\n * @param tokenId Identifier number of a token.\n */\n error ERC721NonexistentToken(uint256 tokenId);\n\n /**\n * @dev Indicates an error related to the ownership over a particular token. Used in transfers.\n * @param sender Address whose tokens are being transferred.\n * @param tokenId Identifier number of a token.\n * @param owner Address of the current owner of a token.\n */\n error ERC721IncorrectOwner(address sender, uint256 tokenId, address owner);\n\n /**\n * @dev Indicates a failure with the token `sender`. Used in transfers.\n * @param sender Address whose tokens are being transferred.\n */\n error ERC721InvalidSender(address sender);\n\n /**\n * @dev Indicates a failure with the token `receiver`. Used in transfers.\n * @param receiver Address to which tokens are being transferred.\n */\n error ERC721InvalidReceiver(address receiver);\n\n /**\n * @dev Indicates a failure with the `operator`’s approval. Used in transfers.\n * @param operator Address that may be allowed to operate on tokens without being their owner.\n * @param tokenId Identifier number of a token.\n */\n error ERC721InsufficientApproval(address operator, uint256 tokenId);\n\n /**\n * @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.\n * @param approver Address initiating an approval operation.\n */\n error ERC721InvalidApprover(address approver);\n\n /**\n * @dev Indicates a failure with the `operator` to be approved. Used in approvals.\n * @param operator Address that may be allowed to operate on tokens without being their owner.\n */\n error ERC721InvalidOperator(address operator);\n}\n\n/**\n * @dev Standard ERC1155 Errors\n * Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC1155 tokens.\n */\ninterface IERC1155Errors {\n /**\n * @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers.\n * @param sender Address whose tokens are being transferred.\n * @param balance Current balance for the interacting account.\n * @param needed Minimum amount required to perform a transfer.\n * @param tokenId Identifier number of a token.\n */\n error ERC1155InsufficientBalance(address sender, uint256 balance, uint256 needed, uint256 tokenId);\n\n /**\n * @dev Indicates a failure with the token `sender`. Used in transfers.\n * @param sender Address whose tokens are being transferred.\n */\n error ERC1155InvalidSender(address sender);\n\n /**\n * @dev Indicates a failure with the token `receiver`. Used in transfers.\n * @param receiver Address to which tokens are being transferred.\n */\n error ERC1155InvalidReceiver(address receiver);\n\n /**\n * @dev Indicates a failure with the `operator`’s approval. Used in transfers.\n * @param operator Address that may be allowed to operate on tokens without being their owner.\n * @param owner Address of the current owner of a token.\n */\n error ERC1155MissingApprovalForAll(address operator, address owner);\n\n /**\n * @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.\n * @param approver Address initiating an approval operation.\n */\n error ERC1155InvalidApprover(address approver);\n\n /**\n * @dev Indicates a failure with the `operator` to be approved. Used in approvals.\n * @param operator Address that may be allowed to operate on tokens without being their owner.\n */\n error ERC1155InvalidOperator(address operator);\n\n /**\n * @dev Indicates an array length mismatch between ids and values in a safeBatchTransferFrom operation.\n * Used in batch transfers.\n * @param idsLength Length of the array of token identifiers\n * @param valuesLength Length of the array of token amounts\n */\n error ERC1155InvalidArrayLength(uint256 idsLength, uint256 valuesLength);\n}\n\n/**\n * @dev Implementation of the {IERC20} interface.\n *\n * This implementation is agnostic to the way tokens are created. This means\n * that a supply mechanism has to be added in a derived contract using {_mint}.\n *\n * TIP: For a detailed writeup see our guide\n * https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How\n * to implement supply mechanisms].\n *\n * The default value of {decimals} is 18. To change this, you should override\n * this function so it returns a different value.\n *\n * We have followed general OpenZeppelin Contracts guidelines: functions revert\n * instead returning `false` on failure. This behavior is nonetheless\n * conventional and does not conflict with the expectations of ERC20\n * applications.\n *\n * Additionally, an {Approval} event is emitted on calls to {transferFrom}.\n * This allows applications to reconstruct the allowance for all accounts just\n * by listening to said events. Other implementations of the EIP may not emit\n * these events, as it isn't required by the specification.\n */\nabstract contract ERC20 is Context, IERC20, IERC20Metadata, IERC20Errors {\n mapping(address account => uint256) private _balances;\n\n mapping(address account => mapping(address spender => uint256)) private _allowances;\n\n uint256 private _totalSupply;\n\n string private _name;\n string private _symbol;\n\n /**\n * @dev Sets the values for {name} and {symbol}.\n *\n * All two of these values are immutable: they can only be set once during\n * construction.\n */\n constructor(string memory name_, string memory symbol_) {\n _name = name_;\n _symbol = symbol_;\n }\n\n /**\n * @dev Returns the name of the token.\n */\n function name() public view virtual returns (string memory) {\n return _name;\n }\n\n /**\n * @dev Returns the symbol of the token, usually a shorter version of the\n * name.\n */\n function symbol() public view virtual returns (string memory) {\n return _symbol;\n }\n\n /**\n * @dev Returns the number of decimals used to get its user representation.\n * For example, if `decimals` equals `2`, a balance of `505` tokens should\n * be displayed to a user as `5.05` (`505 / 10 ** 2`).\n *\n * Tokens usually opt for a value of 18, imitating the relationship between\n * Ether and Wei. This is the default value returned by this function, unless\n * it's overridden.\n *\n * NOTE: This information is only used for _display_ purposes: it in\n * no way affects any of the arithmetic of the contract, including\n * {IERC20-balanceOf} and {IERC20-transfer}.\n */\n function decimals() public view virtual returns (uint8) {\n return 18;\n }\n\n /**\n * @dev See {IERC20-totalSupply}.\n */\n function totalSupply() public view virtual returns (uint256) {\n return _totalSupply;\n }\n\n /**\n * @dev See {IERC20-balanceOf}.\n */\n function balanceOf(address account) public view virtual returns (uint256) {\n return _balances[account];\n }\n\n /**\n * @dev See {IERC20-transfer}.\n *\n * Requirements:\n *\n * - `to` cannot be the zero address.\n * - the caller must have a balance of at least `value`.\n */\n function transfer(address to, uint256 value) public virtual returns (bool) {\n address owner = _msgSender();\n _transfer(owner, to, value);\n return true;\n }\n\n /**\n * @dev See {IERC20-allowance}.\n */\n function allowance(address owner, address spender) public view virtual returns (uint256) {\n return _allowances[owner][spender];\n }\n\n /**\n * @dev See {IERC20-approve}.\n *\n * NOTE: If `value` is the maximum `uint256`, the allowance is not updated on\n * `transferFrom`. This is semantically equivalent to an infinite approval.\n *\n * Requirements:\n *\n * - `spender` cannot be the zero address.\n */\n function approve(address spender, uint256 value) public virtual returns (bool) {\n address owner = _msgSender();\n _approve(owner, spender, value);\n return true;\n }\n\n /**\n * @dev See {IERC20-transferFrom}.\n *\n * Emits an {Approval} event indicating the updated allowance. This is not\n * required by the EIP. See the note at the beginning of {ERC20}.\n *\n * NOTE: Does not update the allowance if the current allowance\n * is the maximum `uint256`.\n *\n * Requirements:\n *\n * - `from` and `to` cannot be the zero address.\n * - `from` must have a balance of at least `value`.\n * - the caller must have allowance for ``from``'s tokens of at least\n * `value`.\n */\n function transferFrom(address from, address to, uint256 value) public virtual returns (bool) {\n address spender = _msgSender();\n _spendAllowance(from, spender, value);\n _transfer(from, to, value);\n return true;\n }\n\n /**\n * @dev Moves a `value` amount of tokens from `from` to `to`.\n *\n * This internal function is equivalent to {transfer}, and can be used to\n * e.g. implement automatic token fees, slashing mechanisms, etc.\n *\n * Emits a {Transfer} event.\n *\n * NOTE: This function is not virtual, {_update} should be overridden instead.\n */\n function _transfer(address from, address to, uint256 value) internal {\n if (from == address(0)) {\n revert ERC20InvalidSender(address(0));\n }\n if (to == address(0)) {\n revert ERC20InvalidReceiver(address(0));\n }\n _update(from, to, value);\n }\n\n /**\n * @dev Transfers a `value` amount of tokens from `from` to `to`, or alternatively mints (or burns) if `from`\n * (or `to`) is the zero address. All customizations to transfers, mints, and burns should be done by overriding\n * this function.\n *\n * Emits a {Transfer} event.\n */\n function _update(address from, address to, uint256 value) internal virtual {\n if (from == address(0)) {\n // Overflow check required: The rest of the code assumes that totalSupply never overflows\n _totalSupply += value;\n } else {\n uint256 fromBalance = _balances[from];\n if (fromBalance < value) {\n revert ERC20InsufficientBalance(from, fromBalance, value);\n }\n unchecked {\n // Overflow not possible: value <= fromBalance <= totalSupply.\n _balances[from] = fromBalance - value;\n }\n }\n\n if (to == address(0)) {\n unchecked {\n // Overflow not possible: value <= totalSupply or value <= fromBalance <= totalSupply.\n _totalSupply -= value;\n }\n } else {\n unchecked {\n // Overflow not possible: balance + value is at most totalSupply, which we know fits into a uint256.\n _balances[to] += value;\n }\n }\n\n emit Transfer(from, to, value);\n }\n\n /**\n * @dev Creates a `value` amount of tokens and assigns them to `account`, by transferring it from address(0).\n * Relies on the `_update` mechanism\n *\n * Emits a {Transfer} event with `from` set to the zero address.\n *\n * NOTE: This function is not virtual, {_update} should be overridden instead.\n */\n function _mint(address account, uint256 value) internal {\n if (account == address(0)) {\n revert ERC20InvalidReceiver(address(0));\n }\n _update(address(0), account, value);\n }\n\n /**\n * @dev Destroys a `value` amount of tokens from `account`, lowering the total supply.\n * Relies on the `_update` mechanism.\n *\n * Emits a {Transfer} event with `to` set to the zero address.\n *\n * NOTE: This function is not virtual, {_update} should be overridden instead\n */\n function _burn(address account, uint256 value) internal {\n if (account == address(0)) {\n revert ERC20InvalidSender(address(0));\n }\n _update(account, address(0), value);\n }\n\n /**\n * @dev Sets `value` as the allowance of `spender` over the `owner` s tokens.\n *\n * This internal function is equivalent to `approve`, and can be used to\n * e.g. set automatic allowances for certain subsystems, etc.\n *\n * Emits an {Approval} event.\n *\n * Requirements:\n *\n * - `owner` cannot be the zero address.\n * - `spender` cannot be the zero address.\n *\n * Overrides to this logic should be done to the variant with an additional `bool emitEvent` argument.\n */\n function _approve(address owner, address spender, uint256 value) internal {\n _approve(owner, spender, value, true);\n }\n\n /**\n * @dev Variant of {_approve} with an optional flag to enable or disable the {Approval} event.\n *\n * By default (when calling {_approve}) the flag is set to true. On the other hand, approval changes made by\n * `_spendAllowance` during the `transferFrom` operation set the flag to false. This saves gas by not emitting any\n * `Approval` event during `transferFrom` operations.\n *\n * Anyone who wishes to continue emitting `Approval` events on the`transferFrom` operation can force the flag to\n * true using the following override:\n * ```\n * function _approve(address owner, address spender, uint256 value, bool) internal virtual override {\n * super._approve(owner, spender, value, true);\n * }\n * ```\n *\n * Requirements are the same as {_approve}.\n */\n function _approve(address owner, address spender, uint256 value, bool emitEvent) internal virtual {\n if (owner == address(0)) {\n revert ERC20InvalidApprover(address(0));\n }\n if (spender == address(0)) {\n revert ERC20InvalidSpender(address(0));\n }\n _allowances[owner][spender] = value;\n if (emitEvent) {\n emit Approval(owner, spender, value);\n }\n }\n\n /**\n * @dev Updates `owner` s allowance for `spender` based on spent `value`.\n *\n * Does not update the allowance value in case of infinite allowance.\n * Revert if not enough allowance is available.\n *\n * Does not emit an {Approval} event.\n */\n function _spendAllowance(address owner, address spender, uint256 value) internal virtual {\n uint256 currentAllowance = allowance(owner, spender);\n if (currentAllowance != type(uint256).max) {\n if (currentAllowance < value) {\n revert ERC20InsufficientAllowance(spender, currentAllowance, value);\n }\n unchecked {\n _approve(owner, spender, currentAllowance - value, false);\n }\n }\n }\n}\n\ninterface IBondToken is IERC20 {\n function mint(address _to, uint256 _value) external;\n function burn(address _from, uint256 _value) external;\n}\n\ncontract BondToken is IBondToken, ERC20, Ownable {\n uint256 public holderCount;\n\n mapping(address => bool) private hasBalance;\n\n constructor(\n string memory _name,\n string memory _symbol,\n uint256 _initialSupply,\n address _owner\n ) ERC20(_name, _symbol) Ownable(_owner) {\n _mint(_owner, _initialSupply); // Mint initial supply to the owner\n }\n\n function migrate() external onlyOwner {\n renounceOwnership();\n }\n\n function mint(address _to, uint256 _value) external onlyOwner {\n _mint(_to, _value);\n }\n\n function burn(address _of, uint256 _value) external onlyOwner {\n _burn(_of, _value);\n }\n\n function isMigrated() external view returns (bool) {\n return owner() == address(0);\n }\n\n // called at mint/burn/transfer\n function _update(address from, address to, uint256 amount) internal override {\n bool isTokenMigrated = owner() == address(0);\n require(\n // if token is not migrated, allow only contract(owner)/burn\n isTokenMigrated || (from == owner() || to == owner() || from == address(0) || to == address(0)),\n \"not migrated yet\"\n );\n\n super._update(from, to, amount);\n\n _updateHolderCount(to, balanceOf(to));\n _updateHolderCount(from, balanceOf(from));\n }\n\n function _updateHolderCount(address _user, uint256 _newBalance) internal {\n bool isCurrentlyHolder = hasBalance[_user];\n bool isStillHolder = _newBalance > 0;\n\n if (isStillHolder && !isCurrentlyHolder) {\n holderCount += 1;\n hasBalance[_user] = true;\n } else if (!isStillHolder && isCurrentlyHolder) {\n holderCount -= 1;\n hasBalance[_user] = false;\n }\n }\n}\n"
}
}
}Last updated