Explore basic types of TypeScript

2 min readNov 6, 2023

Typescript is an object-oriented Programming language that is built on top of JS with extra features.TypeScript is like an extension or “superset” of JavaScript.

# What's wrong with javascript?

not suitable for large applications
lacks strong typing
weird inheritance, unfamiliar syntax
only errors during runtime
suffers type correction

# Benifits of TypeScript

Supports older browser
Type Safety
increase your productivity
less bugs and less testing

# Drawbacks of using Typescript

Type complexities
Limited Libray Support
Over Engineering
Migration challenges

#Install TypeScript and node version

First of all, you download node js from node js website. if you want to switch your node version you should use nvm(node version manager). if you do not know how to install it you can read it.https://www.freecodecamp.org/news/node-version-manager-nvm-install-guide/

// any version download
nvm install node_version

// nvm use command
nvm use node_version

# TypeScript Install

npm install -g typescript

# Write your first TypeScript Program

create a file and ensure that the file extension is ts.

ts package.json file initialization cmd = tsc -init

ts file in root dir (pakage.json)

js file in output dir (pakage.json)

live runnig tsc file cmd = tsc -w

# Explict and union types

// Normal variable
  let a : string | number

//array
  let b : (string | number)[] = []

// object
  let c : object
  let c : {
  name : string,
  age : number
  }

# Dynamic Type

let a : any
let c : {
name : string,
age : number
}

# How to use the function

let myFunc : Function
 myFunc= (a : string, b? : string, c : string = 'string') : string=>
 {

}

# Type Aliases — make your own type

 type typeName = string | number
 type typeName2 = {name : string; age : number}

# Working with class

class Player {
name: string;
age: number;
constructor(n: string, a: number) {
this.name = n;
this.age = a;
}
}

const sakib = new Player("sakib", 36);
const tamim = new Player("tamim", 35);
const musfiq = new Player("sakib", 37);

# Access Modifier

public
private
readonly



class Player {

constructor(
private name : string,
public age : number,
readonly anything : void
) {
this.name = n;
this.age = a;
}
}

# Module System

tsconfig.json

- “target”: “es6”

- “module”: “ES2015”

index.html

script tag type=’’module”