2-packages

2 - Installing and using an NPM package

In this section we will install and use an NPM package. A "package" is simply a piece of code that someone else wrote, and that you can use in your own code. It can be anything. Here, we're going to try a package that helps you manipulate colors for instance.

• Install the community-made package called color by running npm install --save color.

Open package.json to see how --save automatically added color in dependencies.

A node_modules folder has also been created to store the package.

• Create a .gitignore file and put node_modules and npm-debug.log in it (and git init a new repo if you haven't done that yet).

• Add const Color = require('color'); in index.js

• Use the package like this for instance: const redHexa = Color({r: 255, g: 0, b: 0}).hexString();

• Print redHexa, it should show #FF0000

Congratulations, you installed and used an NPM package!

color is just used in this section to teach you how to use a simple package. We won't need it anymore, so you can uninstall it:

• Run npm uninstall --save color

Note: There are 2 kinds of package dependencies, "dependencies" and "devDependencies". "dependencies" is more general than "devDependencies", which are packages that you only need during development, not production (typically, build-related packages, linters, etc). For "devDependencies", we will use the --save-dev parameter instead of --save.

Next section: 3 - Setting up ES6 with Babel and Gulp

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