Installing Babel

06/30/2021

Babel is a JavaScript compiler. This is how to set it up in a project.

Installation

In the terminal, cd into the project directory. Then, you need to create a package.json via:

npm init

Now it's time to install the Babel.js core and CLI libaries:

npm install --save-dev @babel/core @babel/cli

Optional. Install the plugin-proposal-class-properties plugin:

npm install --save-dev @babel/plugin-proposal-class-properties

Usage

Compile the entire src directory and output it to the lib directory by using either --out-dir or -d. This doesn't overwrite any other files or directories in lib.

npx babel src --out-dir lib

Compile the entire src directory and output it as a single concatenated file.

npx babel src --out-file script-compiled.js

To compile a file every time that you change it, use the --watch or -w option:

npx babel script.js --watch --out-file script-compiled.js

Use the --plugins option to specify plugins to use in compilation:

npx babel script.js --out-file script-compiled.js --plugins=@babel/proposal-class-properties,@babel/transform-modules-amd

Use the --presets option to specify presets to use in compilation

npx babel script.js --out-file script-compiled.js --presets=@babel/preset-env,@babel/flow

Further Reading

© 2024 by Ryan Rickgauer