Xiaoyun Yang xiaoyunyang

Bundle Recommendation

Bundle Recommendation
- Overview and Goals
De-scoped

Comments App

Comments App
- Overview and Goals
  - Background
  - User Story
  - Goals
  - Non-Goals
  - Pagination
Frontend trigger for deleting all the comments

Instead of always running source .env before running yarn, you can add your dev secrets like NPM_TOKEN or OPEN_AI_API_KEY to a global dev environmental variable file on your machine (e.g. dev.env) then add this to your .bashrc to source it on startup:

# dev.env
export NPM_TOKEN=<create one in npm settings>

# bashrc
source ~/dev.env

What is nvm?

nvm is a version manager for node.js which lets you easily switch between different node versions. You can define an .nvmrc file in your node project which enforces the node version standardization with your codebase collaborators.

Install NVM

Install

wget -qO- https://raw.githubusercontent.com/nvm-sh/nvm/v0.35.3/install.sh | bash

The example is taken from TypeScript's quick start tutorial

In JavaScript

const greeter = (person) => "hello "+person;
greeter([1,2,3]) // "hello 1,2,3"

In TypeScript

Flow to TypeScript Migration

Helpful Migration Guides:

Migrating a Babel Project to TypeScript

Phase 1: Configure Project to use TypeScript

Delete Flow-related files

What to Test

Testing interfaces

Child component with the right props

import EditProfileForm from "../feedbackForm";
import Checkbox from "../checkbox";
import EmailInput from "../EmailInput";

	import React, { useState } from "react";

	const UiState = {
	LOADING: "LOADING",
	ONLINE: "ONLINE",
	OFFLINE: "OFFLINE",
	};

	const UiStateMessageMap = {
	[UiState.LOADING]: "Loading...",

	import React, { useState } from "react";

	function FriendStatus(props) {
	const [isOnline, setIsOnline] = useState(null);

	useEffect(() => {
	function handleStatusChange(status) {
	setIsOnline(status.isOnline);
	}
	ChatAPI.subscribeToFriendStatus(props.friend.id, handleStatusChange);

	function foo() {
	let res = ''
	let j = 10

	for(let i=0; i<j; i++) {
	// uncommenting ... the following line causes error
	// var j = 5
	res += `${j}, `
	j -= 1
	}