staltz

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

---

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

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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

Stanback

#
# CORS header support
#
# One way to use this is by placing it into a file called "cors_support"
# under your Nginx configuration directory and placing the following
# statement inside your **location** block(s):
#
#   include cors_support;
#
# As of Nginx 1.7.5, add_header supports an "always" parameter which

DawidMyslak

Vue.js and Vuex - best practices for managing your state

Modifying state object

Example

If you have to extend an existing object with additional property, always prefer Vue.set() over Object.assign() (or spread operator).

Example below explains implications for different implementations.

PurpleBooth

Project Title

One Paragraph of project description goes here

Getting Started

These instructions will get you a copy of the project up and running on your local machine for development and testing purposes. See deployment for notes on how to deploy the project on a live system.

Prerequisites

ljharb

Array Iteration

https://gist.github.com/ljharb/58faf1cfcb4e6808f74aae4ef7944cff

While attempting to explain JavaScript's reduce method on arrays, conceptually, I came up with the following - hopefully it's helpful; happy to tweak it if anyone has suggestions.

Intro

JavaScript Arrays have lots of built in methods on their prototype. Some of them mutate - ie, they change the underlying array in-place. Luckily, most of them do not - they instead return an entirely distinct array. Since arrays are conceptually a contiguous list of items, it helps code clarity and maintainability a lot to be able to operate on them in a "functional" way. (I'll also insist on referring to an array as a "list" - although in some languages, List is a native data type, in JS and this post, I'm referring to the concept. Everywhere I use the word "list" you can assume I'm talking about a JS Array) This means, to perform a single operation on the list as a whole ("atomically"), and to return a new list - thus making it mu

paulirish

/* bling.js */

window.$ = document.querySelectorAll.bind(document);

Node.prototype.on = window.on = function (name, fn) {
  this.addEventListener(name, fn);
}

NodeList.prototype.__proto__ = Array.prototype;

EllyLoel

/*
  Made by Elly Loel - https://ellyloel.com/
  With inspiration from:
    - Josh W Comeau - https://courses.joshwcomeau.com/css-for-js/treasure-trove/010-global-styles/
    - Andy Bell - https://piccalil.li/blog/a-modern-css-reset/
    - Adam Argyle - https://unpkg.com/open-props@1.3.16/normalize.min.css / https://codepen.io/argyleink/pen/KKvRORE

  Notes:
    - `:where()` is used to lower specificity for easy overriding.
*/

fgilio

/*
 * Handling Errors using async/await
 * Has to be used inside an async function
 */
try {
    const response = await axios.get('https://your.site/api/v1/bla/ble/bli');
    // Success 🎉
    console.log(response);
} catch (error) {
    // Error 😨

jjmu15

// Determine if an element is in the visible viewport
function isInViewport(element) {
  var rect = element.getBoundingClientRect();
  var html = document.documentElement;
  return (
    rect.top >= 0 &&
    rect.left >= 0 &&
    rect.bottom <= (window.innerHeight || html.clientHeight) &&
    rect.right <= (window.innerWidth || html.clientWidth)
  );