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.

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

leostratus

An ongoing project to catalogue all of these sneaky, hidden, bleeding edge selectors as I prepare my JSConf EU 2012 talk.

Everything is broken up by tag, but within each the selectors aren't particularly ordered.

I have not tested/verified all of these. Have I missed some or got it wrong? Let me know. - A

A friendly reminder that you may need to set this property on your target/selected element to get the styling results you want:

-webkit-appearance:none;

ericelliott

Essential JavaScript Links

I no longer mantain this list. There are lots of other very comprehensive JavaScript link lists out there. Please see those, instead (Google "awesome JavaScript" for a start).

yelouafi

In this tutorial we're going to build a set of parser combinators.

What is a parser combinator?

We'll answer the above question in 2 steps.

1. What is a parser?
2. and, what is a parser combinator?

So first question: What is parser?

ClickerMonkey

// when T is any|unknown, Y is returned, otherwise N
type IsAnyUnknown<T, Y, N> = unknown extends T ? Y : N;
  
// when T is never, Y is returned, otherwise N
type IsNever<T, Y = true, N = false> = [T] extends [never] ? Y : N;

// when T is a tuple, Y is returned, otherwise N
// valid tuples = [string], [string, boolean], 
// invalid tuples = [], string[], (string | number)[]

gaearon

A top-level App component returns <Button /> from its render() method.

1. What is the relationship between <Button /> and this in that Button’s render()?

2. Does rendering <Button><Icon /></Button> guarantee that an Icon mounts?

3. Can the App change anything in the Button output? What and how?

---

davidgilbertson

const http2 = require('http2');
const fs = require('fs');
const path = require('path');
const zlib = require('zlib');
const brotli = require('brotli'); // npm package

const PORT = 3032;
const BROTLI_QUALITY = 11; // slow, but we're caching so who cares
const STATIC_DIRECTORY = path.resolve(__dirname, '../dist/');
const cache = {};

busypeoples

useInView Preact Hook

Can be used as a starting point for implementing your own specific check to see if an element is in view.

const YourViewComponent = () => {
  const { isInView, inViewRef } = useInView();

 return (

andywer

This is a proposal for lightning talk at Reactive Conf. Please 🌟 this gist to push the proposal!

Memory Leak Testing in 2017

Hi, I am Andy, creator of leakage - the node-powered memory leak testing library.

Instead of manual debugging it provides a structured approach to fix or even prevent memory leaks.