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)[]

developit

export const h=(t,p,...c)=>({t,p,c,k:p&&p.key})
export const render=(e,d,t=d.t||(d.t={}),p,r,c,m,y)=>
  // arrays
  e.map?e.map((e,p)=>render(e,d,t.o&&t.o[p])):
  // components
  e.t.call?(e.i=render((render.c=e).t(Object.assign({children:e.c},e.p),e.s=t.s||{},t=>
    render(Object.assign(e.s,t)&&e,d,e)),t.i||d,t&&t.i||{}),d.t=t=e):(
  // create notes
  m=t.d||(e.t?document.createElement(e.t):new Text(e.p)),
  // diff props

gaearon

function mapValues(obj, fn) {
  return Object.keys(obj).reduce((result, key) => {
    result[key] = fn(obj[key], key);
    return result;
  }, {});
}

function pick(obj, fn) {
  return Object.keys(obj).reduce((result, key) => {
    if (fn(obj[key])) {

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

protrolium

ffmpeg

Converting Audio into Different Formats / Sample Rates

Minimal example: transcode from MP3 to WMA:
ffmpeg -i input.mp3 output.wma

You can get the list of supported formats with:
ffmpeg -formats

You can get the list of installed codecs with:

don1138

/* Modern Font Stacks */

/* System */
font-family: system, -apple-system, ".SFNSText-Regular", "San Francisco", "Roboto", "Segoe UI", "Helvetica Neue", "Lucida Grande", sans-serif;

/* System (Bootstrap 5.2.0) */
font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", "Noto Sans", "Liberation Sans", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji";

/* Times New Roman-based serif */
font-family: Cambria, "Hoefler Text", Utopia, "Liberation Serif", "Nimbus Roman No9 L Regular", Times, "Times New Roman", serif;

mjackson

/**
 * Converts an RGB color value to HSL. Conversion formula
 * adapted from http://en.wikipedia.org/wiki/HSL_color_space.
 * Assumes r, g, and b are contained in the set [0, 255] and
 * returns h, s, and l in the set [0, 1].
 *
 * @param   Number  r       The red color value
 * @param   Number  g       The green color value
 * @param   Number  b       The blue color value
 * @return  Array           The HSL representation