Ashik Nesin AshikNesin

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

(also know as lies and/or alternative facts)

js

setImmediate - doesn't set anything immediately, waits for a tick before executing
setTimeout(fn, n) - never sets the timeout to exactly n
Math.random() - computers cannot generate random numbers
Promise - is a lie when rejected
Array.reduce - accumulates, does not reduce (via @sbmadhav)

now.sh notes

Setup

Deployment via docker works great, got something deployed in like ~10m

Running now with a dockerfile + npm, shows > Two manifests found. Press [n] to deploy or re-run with --flag but now help and now deploy help dont show that flag existing, and running now --flag 2 did nothing.

Read the source code, looks like it's refering to the > [1] package.json --npm - --npm bit. Some minor wording

	#!/bin/bash
	files=$(git diff --cached --name-only \| grep '\.jsx\?$')

	# Prevent ESLint help message if no files matched
	if [[ $files = "" ]] ; then
	exit 0
	fi

	failed=0
	for file in ${files}; do

	// See https://blog.isquaredsoftware.com/presentations/react-redux-ts-intro-2020-12/#/36 for slides
	// My basic render function structure:
	function RenderLogicExample({
	someBoolean, // 1) Destructure values from `props` object
	someList,
	}) {
	// 2) Declare state values
	const [a, setA] = useState(0);
	const [b, setB] = useState(0);

	class Sortable extends React.Component {
	componentDidMount() {
	// Every React component has a function that exposes the
	// underlying DOM node that it is wrapping. We can use that
	// DOM node, pass it to jQuery and initialize the plugin.

	// You'll find that many jQuery plugins follow this same pattern
	// and you'll be able to pass the component DOM node to jQuery
	// and call the plugin function.

	// 1. Visit a news website like cnn.com

	// 2. paste this into your console
	setInterval(() =>
	document.querySelectorAll('p,img,a,button,h1,h2,h3,span')
	.forEach(x=>x.style=`transform:rotate(${Math.random()777}deg) scale(${Math.random() 3}); transition:all .5s`)
	, 500);

	// 3. feel a lil bit better 😘

	function validatePath (path) {
	const components = path.split('/');
	const validatedFolderTree = [];

	const getRootFolders = foldersApi.getTopLevelFolders();

	const finalValidationPromise = components.reduce((promise, folder, index) => {
	const folderName = folder.toLowerCase();
	return promise
	.then(parentChildren => {

	// 🔥 Node 7.6 has async/await! Here is a quick run down on how async/await works

	const axios = require('axios'); // promised based requests - like fetch()

	function getCoffee() {
	return new Promise(resolve => {
	setTimeout(() => resolve('☕'), 2000); // it takes 2 seconds to make coffee
	});
	}

	// regex from http://stackoverflow.com/questions/46155/validate-email-address-in-javascript
	const EMAIL_REGEX = /^[-!#$%&'+\/0-9=?A-Z^_a-z{\|}~](\.?[-!#$%&'+\/0-9=?A-Z^_a-z`{\|}~])@[a-zA-Z0-9](-?\.?[a-zA-Z0-9])\.[a-zA-Z](-?[a-zA-Z0-9])+$/;

	const validateEmail = email => {
	return email
	&& email.length < 255
	&& EMAIL_REGEX.test(email);
	};

	export default validateEmail;