// SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/extensions/ERC20Burnable.sol) pragma solidity ^0.8.0; import "../ERC20Upgradeable.sol"; import "../../../utils/ContextUpgradeable.sol"; import "../../../proxy/utils/Initializable.sol"; /** * @dev Extension of {ERC20} that allows token holders to destroy both their own * tokens and those that they have an allowance for, in a way that can be * recognized off-chain (via event analysis). */ abstract contract ERC20BurnableUpgradeable is Initializable, ContextUpgradeable, ERC20Upgradeable { function __ERC20Burnable_init() internal onlyInitializing { } function __ERC20Burnable_init_unchained() internal onlyInitializing { } /** * @dev Destroys `amount` tokens from the caller. * * See {ERC20-_burn}. */ function burn(uint256 amount) public virtual { _burn(_msgSender(), amount); } /** * @dev Destroys `amount` tokens from `account`, deducting from the caller's * allowance. * * See {ERC20-_burn} and {ERC20-allowance}. * * Requirements: * * - the caller must have allowance for ``accounts``'s tokens of at least * `amount`. */ function burnFrom(address account, uint256 amount) public virtual { _spendAllowance(account, _msgSender(), amount); _burn(account, amount); } /** * @dev This empty reserved space is put in place to allow future versions to add new * variables without shifting down storage in the inheritance chain. * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps */ uint256[50] private __gap; }