Kris Kaczor krzkaczor

What is the difference between Cerebral and Redux?

Cerebral and Redux were built to solve different problems

Redux was developed to achieve hot reloading global state and state changing logic. To achieve that it was necessary for state changes to be run with pure functions and the state has to be immutable. Now you can change the logic inside your reducer and when the application reloads Redux will put it in its initial state and rerun all the actions again, now running with the new state changing logic.

Cerebral had no intention of achieving hot reloading. Cerebral was initially developed to give you insight into how your application changes its state, using a debugger. In the Redux debugger you see what actions are triggered and how your state looks after the action was handled. In Cerebral you see all actions fired as part of a signal. You see asynchronous behaviour, paths taken based on decisions made in your state changing flow. You see all inputs and outputs produced during the flow and you even

What happens if you tell GitHub it's JSON

{
  "hello": "world" // I want my comments!
}

Use jsonc as the language instead

Howto: Install Alpine Linux 3.3 on VirtualBox OSX

Latest Standard ISO version x86_64 is recommended (http://alpinelinux.org/downloads/)
Create new VM ("Linux 2.6 / 3.x / 4.x (64-bit)")
1 CPU w/ 512BM RAM and 1 GB default (VDI) disk is more than sufficient
Default networking (NAT)
Boot and add Alpine ISO as attached virtual install media
Default root password is blank (though note - ssh PermitRootLogin defaults to disallow blank passwords and: prohibit-password; switch to yes for Host ssh)
Run setup-alpine
Defaults are fine, but you do want "sys" disk setup to sda, y to confirm

Edit — February 2019

This gist had a far larger impact than I imagined it would, and apparently people are still finding it, so a quick update:

TC39 is currently moving forward with a slightly different version of TLA, referred to as 'variant B', in which a module with TLA doesn't block sibling execution. This vastly reduces the danger of parallelizable work happening in serial and thereby delaying startup, which was the concern that motivated me to write this gist
In the wild, we're seeing (async main(){...}()) as a substitute for TLA. This completely eliminates the blocking problem (yay!) but it's less powerful, and harder to statically analyse (boo). In other words the lack of TLA is causing real problems
Therefore, a version of TLA that solves the original issue is a valuable addition to the language, and I'm in full support of the current proposal, which you can read here.

I'll leave the rest of this document unedited, for archaeological

What I Wish I'd Known About Equity Before Joining A Unicorn

Disclaimer: This piece is written anonymously. The names of a few particular companies are mentioned, but as common examples only.

This is a short write-up on things that I wish I'd known and considered before joining a private company (aka startup, aka unicorn in some cases). I'm not trying to make the case that you should never join a private company, but the power imbalance between founder and employee is extreme, and that potential candidates would

type StringBool = "true"|"false";


interface AnyNumber { prev?: any, isZero: StringBool };
interface PositiveNumber { prev: any, isZero: "false" };

type IsZero<TNumber extends AnyNumber> = TNumber["isZero"];
type Next<TNumber extends AnyNumber> = { prev: TNumber, isZero: "false" };
type Prev<TNumber extends PositiveNumber> = TNumber["prev"];

Achieving warp speed with Rust

	ssh-keygen -t rsa -b 4096 -m PEM -f jwtRS256.key
	# Don't add passphrase
	openssl rsa -in jwtRS256.key -pubout -outform PEM -out jwtRS256.key.pub
	cat jwtRS256.key
	cat jwtRS256.key.pub

	# This program is free software: you can redistribute it and/or modify
	# it under the terms of the GNU General Public License as published by
	# the Free Software Foundation, either version 3 of the License, or
	# (at your option) any later version.
	#
	# This program is distributed in the hope that it will be useful,
	# but WITHOUT ANY WARRANTY; without even the implied warranty of
	# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	# GNU General Public License for more details.
	#

	import * as ts from 'typescript'
	import { Rules, RuleWalker, RuleFailure } from 'tslint'

	function find<T>(collection: T[], predicate: (it: T) => boolean): T \| null {
	for (const item of collection) {
	if (predicate(item)) {
	return item
	}
	}
	return null