Table of Contents

• Modules
  • Accessing the main module
  • Addenda: Package Manager Tips
  • All Together...
  • Caching
    • Module Caching Caveats
  • Core Modules
  • Cycles
  • File Modules
  • Folders as Modules
  • Loading from node_modules Folders
  • Loading from the global folders
  • The module wrapper
  • The module Object
    • module.children
    • module.exports
      • exports shortcut
    • module.filename
    • module.id
    • module.loaded
    • module.parent
    • module.require(id)

Modules#

Stability: 3 - Locked

Node.js has a simple module loading system. In Node.js, files and modules are in one-to-one correspondence (each file is treated as a separate module).

As an example, consider a file named foo.js:

const circle = require('./circle.js');
console.log(`The area of a circle of radius 4 is ${circle.area(4)}`);

On the first line, foo.js loads the module circle.js that is in the same directory as foo.js.

Here are the contents of circle.js:

const PI = Math.PI;

exports.area = (r) => PI * r * r;

exports.circumference = (r) => 2 * PI * r;

The module circle.js has exported the functions area() and circumference()