JavaScript Weekly
Issue 248 — September 4, 2015
Peter Bengtsson of Mozilla looks at using the High Resolution Time API’s now() function for performance measurements.

A dive into ES6’s new ‘let’ and ‘const’ variable declaration features, how they work, and how ‘let’ operates within the dramatically named temporal dead zone.
Nicolas Bevacqua

Eric Elliott looks at the essential ingredients for unit tests and explains some of the art behind writing good unit tests first.
Eric Elliott

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The React team have released all new, fully rewritten developer tools for the popular library. All written in React themselves, Firefox support, full React Native support, and more.

There’s a demo here.
Kagami Hiiragi

An Angular 2 survey got 2100 responses. Opinions on tools and syntax usage were heavily divided, but most Angular 2 users are using TypeScript and WebStorm is the most popular editor.
AngularJS Blog

Falcor is a library from Netflix aiming to change the way webapps request and handle data.
Ryan Chenkie

Introduces a .tsx file extension with support for JSX inside of TypeScript files.


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In Brief

jQuery Foundation and Dojo Foundation to Merge news
Official jQuery Blog

Tabris.js 1.2 Is Out news tools
Mobile Apps with Native UIs from a Single JavaScript Codebase
Tabris.JS  Sponsor

Ember Data v2.0 Released and v2.1 Beta Released news
Like Ember 2.0, Data 2.0 is about removing deprecated functionality, not adding new features.

Scala.js 0.6.5 Released: The Scala to JavaScript Compiler news tools

The JavaScript Misdirection Contest news
Can you hide evil code in plain sight?
Peter Jaric

Computer Vision with Tracking.js Online Hackathon/Contest news

How to Test React Native Apps on a Real iPhone tutorial
Chirag Shah

How to Build A Slackbot and Deploy It to Heroku for Absolute Beginners tutorial
Shivani Negi

ES6 Classes in Depth tutorial
Nicolas Bevacqua

Defusing Race Conditions when Using Promises tutorial
Alex Johnson

Unimorphic Isoversal JavaScript What? opinion
Kyle Simpson

10 Essential Sublime Text Plugins for JavaScript Developers tools

Real Time Error Reporting in Minutes. Try Raygun Free for 30 Days tools
Full stack support detailed diagnostic information lets you resolve errors before they impact your users.
Raygun   Sponsor

Minigrid: Zero-Dependency 2KB Cascading Grid Layout code
Henrique Alves

Substance: A Library for Web-Based Content Editing code
Flexible enough to use simply as-is or to define your own custom editors.
Substance Software GmbH

combinatorics.js: Combinatorics JavaScript Library code
Devan Patel

React CSS Modules: Mapping of Class Names to CSS Modules in React Components code
Gajus Kuizinas

Automata.js: Regular Expression to FSM Converter code
Haojian Wu

Wallop: Minimal Library for 'Showing and Hiding Things' code
Takes a collection of HTML elements, previous and next buttons, and makes it all work.
Pedro Duarte

Bad City: A GTA-style Multiplayer Browser Game Written in JavaScript demo
It’s lo-fi and collapses under traffic but.. we've enjoyed this at CooperPress HQ (we might even try joining for a while after sending this issue ;-)). Good luck.