Fallback과 Receive함수는 둘 다 이더를 전송 받을 때 사용되는 함수이다.그러나 두 함수에 몇가지 차이점도 있고 헷갈리는 부분이 있어 정리할려 한다. 공통점- 상대방이 이더를 전송해서 내 컨트랙트에서 이더를 받을 때 실행된다. 차이점순수하게 이더만 전송할때는 Receive()이더와 데이터를 포함하여 전송 또는 잘못된 함수를 호출할때 Fallback()함수가 호출된다.예를 들어,contractAddress.call{value: 1 ether}();는 Receive함수를contractAddress.call{value: 1 ether}("someData");는 Fallback 함수를 호출한다. 다만, 순수하게 이더만 전송할 때, Receive함수가 없고 Fallback 함수만 있으면 Fallback..
Web3
// SPDX-License-Identifier: MITpragma solidity ^0.5.0;import "../helpers/Ownable-05.sol";contract AlienCodex is Ownable { bool public contact; bytes32[] public codex; modifier contacted() { assert(contact); _; } function makeContact() public { contact = true; } function record(bytes32 _content) public contacted { codex.push(_content); } func..
To solve this level, you only need to provide the Ethernaut with a Solver, a contract that responds to whatIsTheMeaningOfLife() with the right 32 byte number.Easy right? Well... there's a catch.The solver's code needs to be really tiny. Really reaaaaaallly tiny. Like freakin' really really itty-bitty tiny: 10 bytes at most.Hint: Perhaps its time to leave the comfort of the Solidity compiler mome..
// SPDX-License-Identifier: MITpragma solidity ^0.8.0;contract Recovery { //generate tokens function generateToken(string memory _name, uint256 _initialSupply) public { new SimpleToken(_name, msg.sender, _initialSupply); }}contract SimpleToken { string public name; mapping(address => uint256) public balances; // constructor constructor(string memory _name, address _cr..
// SPDX-License-Identifier: MITpragma solidity ^0.8.0;contract Preservation { // public library contracts address public timeZone1Library; address public timeZone2Library; address public owner; uint256 storedTime; // Sets the function signature for delegatecall bytes4 constant setTimeSignature = bytes4(keccak256("setTime(uint256)")); constructor(address _timeZone1LibraryA..
