Node-based compilation

The simplest and leanest TypeScript development environment consists of a simple text editor, and a Node-based TypeScript compiler. Head over to the Node website (https://nodejs.org/) and follow the instructions to install Node on your operating system of choice.

Once Node is installed, TypeScript can be installed by simply typing the following:

npm install -g typescript

This command invokes the Node Package Manager (npm) to install TypeScript as a global module (the -g option), which will make it available no matter what directory we are currently in. Once TypeScript has been installed, we can display the current version of the compiler by typing the following:

tsc -v

At the time of writing, the TypeScript compiler is at version 3.3.3, and therefore the output of this command is as follows:

Version 3.3.3

Let's now create a TypeScript file named hello.ts with the following content:

console.log('hello TypeScript'); 

From the command line, we can use TypeScript to compile this file into a JavaScript file by issuing the following command:

tsc hello.ts 

Once the TypeScript compiler has completed, it will have generated a hello.js file in the current directory. We can run this file using Node by typing the following:

node hello.js

This will output the following to the console:

hello TypeScript