taiseen/learning-typeScript

28 - April - 2023

TypeScript Learning

In this repo has 3 category TypeScript learning domain...

1) Raw TypeScript                   ===> ./src/script/

2) HTML, CSS + TypeScript project   ===> ./src/script/ts/nn/

3) React with TypeScript            ===> ./src/

• yarn create vite --template react-ts PROJECT_NAME
• yarn add -D tailwindcss postcss autoprefixer
• npx tailwindcss init -p
• yarn add -D @types/node
• yarn add -D ts-node-dev

nvm list

nvm install 18.16.0

nvm use 18.16.0 [run as administrator at cmd]

for command-line typeScript file compiling type --> tsc

NOTE:- if you run normal typeScript file at command-line by [node fileName.js] then...
at "tsconfig.json" file set...

🟥 "watch" : true,

so this option always watch - our souse code, when we save the file every time...
& that will just recompile our [.ts] source code file into [.js] file...


🟥 "target": "es2016" ==> to ==> 
🟥 "target": "esnext"

for async/await native support...

use "types" when building "applications" & 
use "interfaces" when building "libraries"

Learning Context:-

• these things, we'll probably memorize, without even realizing...

No	Context	Short Form
1	primitive type	string, number, boolean
2	object type	{ }
3	array type | array of objects type	{ }[ ]
4	union of string literal types - not allow any random string	'loading' | 'error' | 'success'
5	children prop	children: string
6	children prop when its React Component	children: React.ReactNode
7	optional prop type	extraSubject?: string
8	empty event prop onClick	handleClick: () => void
9	with event prop onClick	handleClickEvent: (e: React.MouseEvent<HTMLButtonElement>) =>
10	with id prop onClick	handleClickId: (id: number) => void
11	input type prop onChange	handleChange: (e: React.ChangeEvent<HTMLInputElement>) =>
12	inline css prop type	style: React.CSSProperties
13	useState type	useState<null | User>(null) <-- value come at future
14	useReducer type	Mother = Child1 | Child2 <-- Discriminated Unions
15	createContext type	( { } as UserContextProps ) <-- Type Assertion

[note]
an "automated test" is code that throws an error, 
when the actual output does not match the expected output...

it will pass when the output is correct & 
provide meaningful feedback when it is not