RareSkills

interface IExampleInterface {
	event Deposit(address indexed sender, uint256 amount);
}

contract ExampleContract is IExampleInterface {
	function deposit() external payable {
		emit Deposit(msg.sender, msg.value);
	}
}

RareSkills

contract ParentContract {
  event NewNumber(uint256 number);

  function doSomething(uint256 number) public {
    emit NewNumber(number);
  }
}

contract ChildContract is ParentContract {

RareSkills

pragma solidity ^0.8.15;
contract ExampleContract {

    event SomeEvent(uint256 blocknum, uint256 indexed timestamp);

    function selector() external pure returns (bool) {

        // true
 return SomeEvent.selector == keccak256("SomeEvent(uint256,uint256)");

RareSkills

```solidity
pragma solidity ^0.8.15;
contract ExampleContract {

    event SomeEvent(uint256 blocknum, uint256 indexed timestamp);

    function selector() external pure returns (bool) {

        // true
        return SomeEvent.selector == keccak256("SomeEvent(uint256,uint256)");

RareSkills

pragma solidity ^0.8.15;
contract ExampleContract {

    event SomeEvent(uint256 blocknum, uint256 timestamp) anonymous;

    function selector() public pure returns (bool) {

        // ERROR: does not compile, anonymous events don't have selectors
 return SomeEvent.selector == keccak256("SomeEvent(uint256,uint256)");

RareSkills

op code	Usage
log0(p, s)	log without topics and data mem[p…(p+s))
log1(p, s, t1)	log with topic t1 and data mem[p…(p+s))
log2(p, s, t1, t2)	log with topics t1, t2 and data mem[p…(p+s))
log3(p, s, t1, t2, t3)	log with topics t1, t2, t3 and data mem[p…(p+s))
log4(p, s, t1, t2, t3, t4)	log with topics t1, t2, t3, t4 and data mem[p…(p+s))

RareSkills

const ethers = require('ethers');

const tokenAddress = '0x...';

const filterAddress = '0x...';

const tokenAbi = [
  // ...
];

RareSkills

const { ethers } = require("ethers");

// const provider = your provider

const abi = [
  "event Transfer(address indexed from, address indexed to, uint256 value)"
];

const tokenAddress = "0x...";
const contract = new ethers.Contract(tokenAddress, abi, provider);

RareSkills

contract ExampleContract {

  // We will explain the significance of the indexed parameter later.
  event ExampleEvent(address indexed sender, uint256 someValue);

  function exampleFunction(uint256 someValue) public {
    emit ExampleEvent(sender, someValue);
  }
}

RareSkills

import { ethers } from "hardhat";

async function main() {
  const [user] = await ethers.getSigners();
  const data = "0x5197c7aa"; // function selector for the `getX` function

  const Slot = await ethers.getContractFactory("Wrong");
  const slot = await Slot.deploy();
  await slot.deployed();