How JavaScript's '==' actually works, step by step

#427 — March 8, 2019 Read on the Web JavaScript Weekly Handtrack.js: Realtime Hand Detection, Directly in the Browser — A neat way to prototype hand-related gestures or interactions in the browser in very few lines of code. Naturally, there's a live demo, there's also a CodePen you can play with, or just the plain ole' GitHub repo. Victor Dibia JavaScript Performance Pitfalls in V8 — A very detailed article where Benedikt Meurer of the core V8 team shows how V8 compiles your code and shares some tricks you can use to avoid performance problems. Benedikt Meurer Don’t Miss the New Developer Track at Slack’s Annual Conference — Whether you’re new to Slack or an expert app builder, there’s something for everyone at Frontiers, including a developer track designed just for you. Attend workshops, new feature demos, one-on-one advice sessions, and more. Register today to reserve your spot. Slack sponsor How Loose Comparisons (==) Work Step-by-Step — Determining what’s equal in JavaScript when you use == (versus ===) is notoriously tricky but this quick tool demonstrates the process JavaScript takes to figure it out - you can put your own values in to play around too. Felix Kling JavaScript Symbols: But Why? — Not played with symbols (a new data type introduced with ES6) yet? This is a gentle way to get up to speed with not only what they are but why you might use them. Thomas Hunter II The Third Party Web of Excessive JavaScript Execution — Research shows that across the top 1 million Web sites, just 800 origins account for 65% of all script execution time. Which third party scripts are slowing down the Web? Patrick Hulce Storybook 5.0: The UI Component Workshop — Storybook is a popular tool for building UI components for React, Angular, and Vue.js apps, now with an all-new interface. Wondering why you should use Storybook? They’ve got that covered in this 2 minute intro video. Michael Shilman 💻 Jobs JavaScript Developer at X-Team (Remote) — Join the most energizing community for developers. Work from anywhere with the world's leading brands. X-Team Senior Software Engineer - Invoca (Santa Barbara, or Remote US) — Join our collaborative engineering team, deploying code to our production SaaS platform & public cloud infrastructure. Invoca Find A Job Through Vettery — Vettery specializes in dev roles and is completely free for job seekers. Vettery 📘 Tutorials and Opinions What the Functor? Functional Terminology Explained with JS — We recently linked to a neat jargon-free intro to functional programming concepts and the author is now back with… an introduction to some of the jargon! Functors, categories, endofunctors, monoids, and monads are deftly explained here. Matthew Gerstman ▶  How Google Search Indexes JavaScript Sites — Martin Splitt briefly explains how JavaScript influences SEO and how to optimize your JavaScript-powered website to be search-friendly. Google Webmasters Get Up to Speed in Building Web Applications with Node.js — Learn the basics, and gain proficiency in building, testing, and deploying apps in the cloud through concrete examples & practical projects. Microsoft Azure sponsor How Does Aurelia 'React'? — Aurelia is an interesting framework in its own right - this new series aims to show how Aurelia approaches things you might otherwise do in React. Rob Eisenberg ▶  Discussing Maintaining Vue.js with Evan You — An hour long podcast chat with the maintainer of Vue.js. ShopTalk podcast Building a Plasma Canvas Effect with Rust and WebAssembly — Yes, the actual effect is coded in Rust, but JavaScript is used to bring everything together and may be of interest to you if you want to bring other languages into your frontend development via WebAssembly. Jeremy Likness Executing Arrays of async/await Functions in Series vs. Concurrently Corey Cleary 🔧 Code and Tools Cherow: A Fast, Standards-Compliant JavaScript Parser — Parses right up to ECMAScript 2020(!) and there’s a live demo so you can see what it outputs. KFlash Use Sencha’s Powerful Grid for Your React Apps — Grids can be frustrating to build. Save time: Easily integrate our pre-built grid & 115+ components into your React app. Sencha, Inc. sponsor A Naive, 27 Line Reimplementation of React Hooks — OK, it’s hard to read and there’s a (minor) bug in it, but reading through this code example might help you understand how hooks work under the surface a little more. Here’s an interactive, copy/pasteable alternative you can play with yourself. Shawn Wang iro.js: An SVG-Based HSV Color Picker Widget — Live demo and code example. James Rakujira NLP.js: Natural Language Utilities for Node.js — Guess the language of a text, stemming/tokenization, sentiment analysis, etc. AXA Share Your Whole Stack with Your Team with One Workflow 👩‍💻 Manifold sponsor Ink 2.0: Like React, But For Building CLI Apps — A component-based UI building experience, but for CLI apps. Vadim Demedes React-Calendar: A Simple Calendar Component — A straightforward, compact monthly view. (BTW, if you want more React libraries and components, you’ll enjoy our React newsletter, which is where most of them go! 😄) Wojciech Maj AV1: AVIF (AV1 Still Image Format) Polyfill for the Browser — AVIF is a image format whose spec has just reached version 1.0. Kagami Hiiragi

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