developit

/** Usage:
 *    const MyView = unrecycle(props => {
 *      // this is normally a no-go and creates leaking styles, but it won't with unrecycle():
 *      <input ref={ c => c && c.style.background='red' } />  
 *    })
 */
export default function unrecycle(Component) {
  return function Unrecycle(props, context) {
  	this.componentWillUnmount = dontRecycle;
    return Component.call(this, props, context);

pgilad

Generate private key

$ openssl genrsa -out private.key 4096

Generate a Certificate Signing Request

openssl req -new -sha256 \

DaBs

var str = 'class ಠ_ಠ extends Array {constructor(j = "a", ...c) {const q = (({u: e}) => {return { [`s${c}`]: Symbol(j) };})({});super(j, q, ...c);}}' + 
          'new Promise((f) => {const a = function* (){return "\u{20BB7}".match(/./u)[0].length === 2 || true;};for (let vre of a()) {' +
          'const [uw, as, he, re] = [new Set(), new WeakSet(), new Map(), new WeakMap()];break;}f(new Proxy({}, {get: (han, h) => h in han ? han[h] ' + 
          ': "42".repeat(0o10)}));}).then(bi => new ಠ_ಠ(bi.rd));';

try {
  eval(str);
} catch(e) {
  alert('Your browser does not support ES6!')
}

Rich-Harris

Stuff I wish I'd known sooner about service workers

I recently had several days of extremely frustrating experiences with service workers. Here are a few things I've since learned which would have made my life much easier but which isn't particularly obvious from most of the blog posts and videos I've seen.

I'll add to this list over time – suggested additions welcome in the comments or via twitter.com/rich_harris.

Use Canary for development instead of Chrome stable

Chrome 51 has some pretty wild behaviour related to console.log in service workers. Canary doesn't, and it has a load of really good service worker related stuff in devtools.

bastman

Docker - How to cleanup (unused) resources

Once in a while, you may need to cleanup resources (containers, volumes, images, networks) ...

delete volumes

// see: https://github.com/chadoe/docker-cleanup-volumes

$ docker volume rm $(docker volume ls -qf dangling=true)

$ docker volume ls -qf dangling=true | xargs -r docker volume rm

paulirish

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

isaacs

# Hello, and welcome to makefile basics.
#
# You will learn why `make` is so great, and why, despite its "weird" syntax,
# it is actually a highly expressive, efficient, and powerful way to build
# programs.
#
# Once you're done here, go to
# http://www.gnu.org/software/make/manual/make.html
# to learn SOOOO much more.

addyosmani

CSS Layout Debugger

A tweet-sized debugger for visualizing your CSS layouts. Outlines every DOM element on your page a random (valid) CSS hex color.

One-line version to paste in your DevTools

Use $$ if your browser aliases it:

~ 108 byte version

kevin-smets

Default

Powerlevel10k

PaulKinlan

(function() { 
  var CSSCriticalPath = function(w, d, opts) {
    var opt = opts || {};
    var css = {};
    var pushCSS = function(r) {
      if(!!css[r.selectorText] === false) css[r.selectorText] = {};
      var styles = r.style.cssText.split(/;(?![A-Za-z0-9])/);
      for(var i = 0; i < styles.length; i++) {
        if(!!styles[i] === false) continue;
        var pair = styles[i].split(": ");