Andrei Simion andreiashu

4.3 The Block

The block in Ethereum is the collection of relevant pieces of information (known as the block header), together with information corresponding to the comprised transactions, and a set of other block headers that are known to have a parent equal to the present block’s parent’s parent (such blocks are known as uncles).

https://sourcegraph.com/github.com/ethereum/go-ethereum@479aa61f11724560c63a7b56084259552892819d/-/blob/core/types/block.go#L139

type Block struct {
	header       *Header
	uncles []*Header

Git DMZ Flow

I've been asked a few times over the last few months to put together a full write-up of the Git workflow we use at RichRelevance (and at Precog before), since I have referenced it in passing quite a few times in tweets and in person. The workflow is appreciably different from GitFlow and its derivatives, and thus it brings with it a different set of tradeoffs and optimizations. To that end, it would probably be helpful to go over exactly what workflow benefits I find to be beneficial or even necessary.

Two developers working on independent features must never be blocked by each other
- No code freeze! Ever! For any reason!
A developer must be able to base derivative work on another developer's work, without waiting for any third party
Two developers working on inter-dependent features (or even the same feature) must be able to do so without interference from (or interfering with) any other parties
Developers must be able to work on multiple features simultaneously, or at lea

	// SPDX-License-Identifier: MIT

	pragma solidity 0.8.11;

	contract MappingBool {

	// NB: if you need to distinguish from nil vs false this method does not work
	mapping(address => bool) entries;

	// gas 44463

	// paste this in your browser's console
	(function() {
	_loadScript = function(path){ var script= document.createElement('script'); script.type= 'text/javascript'; script.src= path; document.head.appendChild(script); }

	_loadScript('https://cdn.jsdelivr.net/npm/[email protected]/dist/ethers.umd.js');

	// @TODO: this can fail on slow connections; should have a retry mechanism
	setTimeout(() => {
	console.log(`Loaded ethersjs version: ${ethers.version}`);
	}, 1500);

	// paste this in your browser's console
	(function() {
	_loadScript = function(path){ var script= document.createElement('script'); script.type= 'text/javascript'; script.src= path; document.head.appendChild(script); }

	_loadScript('https://cdnjs.cloudflare.com/ajax/libs/web3/1.6.1-rc.0/web3.min.js');

	// @TODO: this can fail on slow connections; should have a retry mechanism
	setTimeout(() => {
	console.log(`Loaded Web3 version: ${Web3.version}`);
	}, 1500);

	describe("Understand Jest framework", () => {
	test("async works with Promise.resolve", async () => Promise.resolve(true))
	test("async works with return", async () => true)
	test("async works with expect met", async () => expect(true).toBe(true))
	test("expect throws", async () => {
	try {
	expect(true).toBe(false)
	console.log('This should not be printed')
	} catch (err) {
	// silence the error

	# PWN that sucker!
	# Warning: completely obliterates Docker: removes all containers, images and volumes
	# add this function to your ~/.bash_profile or ~/.zshrc (or equivalent)
	pwndocker() {
	echo -n "You sure you want to pwn Docker (y/n)? "
	read answer
	if echo "$answer" \| grep -iq "^y$" ;then
	[[ -n $(docker ps -qa) ]] && docker kill $(docker ps -qa)
	[[ -n $(docker ps -qa) ]] && docker rm -v $(docker ps -qa)
	[[ -n $(docker images -q) ]] && docker rmi -f $(docker images -q)

	CREATE TABLE `datapoints` (
	`id` int(11) unsigned NOT NULL AUTO_INCREMENT,
	`lineid` varchar(255) DEFAULT NULL,
	`geolocation` point DEFAULT NULL,
	`price` float NOT NULL,
	`currency` varchar(20) NOT NULL DEFAULT '',
	`locname` text DEFAULT NULL,
	`time` datetime DEFAULT NULL,
	PRIMARY KEY (`id`)
	) ENGINE=InnoDB AUTO_INCREMENT=8 DEFAULT CHARSET=utf8;

	const Promise = require('bluebird');

	// bluebird unhandledRejection event
	process.on('unhandledRejection', function (reason, promise) {
	console.log(`unhandledRejection, reason ${reason}`, promise);
	// don't continue in this state you plonker!
	process.exit(1);
	});