joeytwiddle

Do not use forEach with async-await

TLDR: Use for...of instead of forEach() in asynchronous code.

For legacy browsers, use for...i or [].reduce()

To execute the promises in parallel, use Promise.all([].map(...))

The problem

poteto

const MESSAGES = {
  400(foo) { 
    // stuff
  },
  404(foo) {
    // stuff
  },
  500(foo) {
    // stuff
  }

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

ryanflorence

Folder Structure

Please note

While this gist has been shared and followed for years, I regret not giving more background. It was originally a gist for the engineering org I was in, not a "general suggestion" for any React app.

Typically I avoid folders altogether. Heck, I even avoid new files. If I can build an app with one 2000 line file I will. New files and folders are a pain.

rwjblue

• Data Down / Actions Up

  • http://emberjs.jsbin.com/nayaho/edit?html,js - Interdependent select boxes. No observers.
  • http://ember-twiddle.com/2d7246875098d0dbb4a4 - One Way Input

• Plain JSBin's

  • http://rwjblue.jsbin.com/pixeki/edit?html,js,output

• Ember Version Base JSBin's

  • 1.0 - http://emberjs.jsbin.com/juluje/edit?html,js,output

• 1.1 - http://emberjs.jsbin.com/cofufo/edit?html,js,output

sebastianseilund

/**
 * `Ember.MergedArray` is an array that observes multiple other arrays (called source arrays) for changes and includes
 * all items from all source arrays in an efficient way.
 * 
 * Usage:
 * 
 * ```javascript
 * var obj = Ember.Object.create({
 *   people: [
 *      {