guest271314

• V8

V8 is Google’s open source high-performance JavaScript and WebAssembly engine, written in C++. It is used in Chrome and in Node.js, among others. It implements ECMAScript and WebAssembly, and runs on Windows 7 or later, macOS 10.12+, and Linux systems that use x64, IA-32, ARM, or MIPS processors. V8 can run standalone, or can be embedded into any C++ application.

• SpiderMonkey

SpiderMonkey is Mozilla’s JavaScript and WebAssembly Engine, used in Firefox, Servo and various other projects. It is written in C++, Rust and JavaScript. You can embed it into C++ and Rust projects, and it can be run as a stand-alone shell. It can also be [compiled](https://bytecodealliance.org/articles/making-javascript-run-fast-on

getify

In defense of blocks for local scopes (Part 2)

Some have leveled the criticism that "part 1" of this post is unnecessarily contriving a problem that doesn't really exist in "good code" -- if you really need to narrow a scope of some declarations in a function, then that function is too complex already and that bigger problem is what you need to fix.

Just to be extra clear: if a chunk of code is already reasonable to make a function, that's not the sort of code I'm talking about in either of these blog posts. If it's being called multiple times, or if it's completely independent and makes sense as its own logical chunk, make it a function. I'm talking about a different sort of code, a set of a few statements related to each other, that declare one or more variables, but which logically still belong inside another function. That's the context here.

OK, let's stop talking about this stuff abstractly.

A Real Example

sindresorhus

Pure ESM package

The package that linked you here is now pure ESM. It cannot be require()'d from CommonJS.

This means you have the following choices:

1. Use ESM yourself. (preferred)
   Use import foo from 'foo' instead of const foo = require('foo') to import the package. You also need to put "type": "module" in your package.json and more. Follow the below guide.
2. If the package is used in an async context, you could use await import(…) from CommonJS instead of require(…).
3. Stay on the existing version of the package until you can move to ESM.

JamieCurnow

/**
 * This Gist is part of a medium article - read here:
 * https://jamiecurnow.medium.com/using-firestore-with-typescript-65bd2a602945
 */

// import firstore (obviously)
import { firestore } from "firebase-admin"

// Import or define your types
// import { YourType } from '~/@types'

developit

module.exports = {
	env: {
		browser: true
	},
	extends: [
		'plugin:react/recommended',
		'plugin:@typescript-eslint/recommended',
		'prettier/@typescript-eslint',
		'plugin:prettier/recommended'
	],

slikts

Advanced memoization and effects in React

Memoization is a somewhat fraught topic in the React world, meaning that it's easy to go wrong with it, for example, by [making memo() do nothing][memo-pitfall] by passing in children to a component. The general advice is to avoid memoization until the profiler tells you to optimize, but not all use cases are general, and even in the general use case you can find tricky nuances.

Discussing this topic requires some groundwork about the technical terms, and I'm placing these in once place so that it's easy to skim and skip over:

• Memoization means caching the output based on the input; in the case of functions, it means caching the return value based on the arguments.
• Values and references are unfortunately overloaded terms that can refer to the low-level implementation details of assignments in a language like C++, for example, or to memory

JoeyBurzynski

58 bytes of CSS to look great nearly everywhere

When making this website, i wanted a simple, reasonable way to make it look good on most displays. Not counting any minimization techniques, the following 58 bytes worked well for me:

main {
  max-width: 38rem;
  padding: 2rem;
  margin: auto;
}

datchley

React/Redux Style Guide

Table of Contents:

• React/Redux Style Guide
  • React Guidelines
    • Organization
    • Components
• Container Components

xbeta

http://stackoverflow.com/questions/24380159/corebluetooth-and-wifi-interference

http://lists.apple.com/archives/bluetooth-dev/2013/Aug/msg00023.html

This is a well known issue, and it has a solution that is confirmed to work for the Mac side.

sudo defaults write /Library/Preferences/com.apple.airport.bt.plist bluetoothCoexMgmt Hybrid

After you run this script, the issue will go away and BT connections will remain stable.

suissa

var ffmpeg = require('ffmpeg');

try {
  var process = new ffmpeg('example.mp4');
  process.then(function (video) {
    console.log('The video is ready to be processed');
    var watermarkPath = 'watermark-suissa.png',
      newFilepath = './video-com-watermark.mp4',
      settings = {
          position        : "SE"      // Position: NE NC NW SE SC SW C CE CW