Security · medium

32. Reentrancy guard

Block recursive calls.

Implement a `nonReentrant` modifier using a uint256 status flag.

Required in your answer: modifier nonReentrantrequire(_status == 1_status = 2_status = 1;

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// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;

contract Guard {
    uint256 private _status = 1;
    // TODO nonReentrant
    function safe() external /* TODO */ {}
}

Output appears here.

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