Nathan Kleyn nathankleyn

The introduction to Reactive Programming you've been missing

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

New Code: https://github.com/killercup/trpl-ebook

New Download Links (EPUB, PDF, etc.): http://killercup.github.io/trpl-ebook/

What forces layout / reflow

All of the below properties or methods, when requested/called in JavaScript, will trigger the browser to synchronously calculate the style and layout*. This is also called reflow or layout thrashing, and is common performance bottleneck.

Generally, all APIs that synchronously provide layout metrics will trigger forced reflow / layout. Read on for additional cases and details.

Element APIs

Getting box metrics

elem.offsetLeft, elem.offsetTop, elem.offsetWidth, elem.offsetHeight, elem.offsetParent

Strictly Frameworks

Mobiledoc - github.com/bustle/mobiledoc-kit - framework to build editors with a standardized JSON structure
ShareDB - github.com/share/sharedb - framework to sync any JSON document using operational transforms, add real-time collaborative editing to anything else
Bangle.dev - github.com/bangle-io/bangle.dev - toolkit built for building editors, based on prosemirror

Abstracted Editors

These use separate document structures instead of HTML, some are more modular libraries than full editors

Turning Off Github Issues

My friend Michael Jackson turned off github issues on one of his smaller projects. It got me thinking...

Maintainers getting burned out is a problem. Not just for the users of a project but the mental health of the maintainer. It's a big deal for both parties. Consumers want great tools, maintainers want to create them, but maintainers don't want to be L1 tech support, that's why they

Creating a redis Module in 15 lines of code!

A quick guide to write a very very simple "ECHO" style module to redis and load it. It's not really useful of course, but the idea is to illustrate how little boilerplate it takes.

Step 1: open your favorite editor and write/paste the following code in a file called module.c

#include "redismodule.h"
/* ECHO <string> - Echo back a string sent from the client */
int EchoCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {

	Introduction
	============

	Futoshiki (不等式, meaning “inequality”) is a Japanese logic puzzle similar to
	Sudoku and the like. Numbers from 1 to n must be placed on an n-by-n grid
	(which usually already contains some values) such that each row and each column
	is a permutation of `[1..n]`. Additionally, less-than or greater-than signs are
	placed between cells, constraining their mutual ordering.

	An example puzzle looks like this:

	{-# LANGUAGE ConstraintKinds #-}
	{-# LANGUAGE GeneralizedNewtypeDeriving #-}

	module ParserCombinators where

	{-

	We'll build a set of parser combinators from scratch demonstrating how
	they arise as a monad transformer stack. Actually, how they arise as a
	choice between two different monad transformer stacks!

	function transfer
	if test (count $argv) -eq 0
	echo "No arguments specified. Usage:\necho transfer /tmp/test.md\ncat /tmp/test.md \| transfer test.md"
	return 1
	end

	## get temporarily filename, output is written to this file show progress can be showed
	set tmpfile ( mktemp -t transferXXX )

	## upload stdin or file