TypeScript Getting Started

TypeScript being converted into JavaScript means it runs anywhere that JavaScript runs!

TypeScript Compiler

TypeScript is transpiled into JavaScript using a compiler.

Installing the Compiler

TypeScript has an official compiler which can be installed through npm.

Within your npm project, run the following command to install the compiler:

npm install typescript --save-dev

Which should give you an output similar to:

added 1 package, and audited 2 packages in 2s
found 0 vulnerabilities

The compiler is installed in the node_modules directory and can be run with: npx tsc.

npx tsc

Which should give you an output similar to:

Version 4.5.5
tsc: The TypeScript Compiler - Version 4.5.5

Followed by a list of all the Commmon Commands.

Configuring the compiler

By default the TypeScript compiler will print a help message when run in an empty project.

The compiler can be configured using a tsconfig.json file.

You can have TypeScript create tsconfig.json with the recommended settings with:

npx tsc --init

Which should give you an output similar to:

Created a new tsconfig.json with:
TS
  target: es2016
  module: commonjs
  strict: true
  esModuleInterop: true
  skipLibCheck: true
  forceConsistentCasingInFileNames: true

You can learn more at https://aka.ms/tsconfig.json

Here is an example of more things you could add to the tsconfig.json file:

{
  "include": ["src"],
  "compilerOptions": {
    "outDir": "./build"
  }
}

You can open the file in an editor to add those options. This will configure the TypeScript compiler to transpile TypeScript files located in the src/ directory of your project, into JavaScript files in the build/ directory.

.json