# 📦 Modules

2 min read, 212 words es2015 modules javascript import export

Originally JS had no concept of modules and export, import
- dark ages of JavaScript
Starting with ECMAScript 2015 (opens new window), JavaScript has a concept of modules.
Modules have their own name-spaces, unless they are exported

export = className;

// compiles to CommonJS module export syntax
module.exports = className;

// ES6 modules export
export default varName;

// commonJS module export
module.exports = varName;

Difference b/w module.exports.foo and exports.foo ? (opens new window)

# 🚦 Interface

shape of data

Interface Example (opens new window)

# Modules Systems in JS world?

# 🌩 Good questions

When should I use curly braces for ES6 import?: default import vs Named import

// export default 42
import A from "ABC";

// export const A = 42
import { A } from "ABC";

// Default export is actually a named export with name default
import { default as Sample } from "../Sample.js";

source (opens new window)

# ⭐️ Main Features

Arrows and Lexical this
Classes
Templated strings
Object/Array Destructuring
1. fail-soft
Default + Rest + Spread
Let + Const
for ... of Iterator
Generators function* and yield
Modules export/import
Promises - asynchronous programming

# 🌎 Resources

← Javascript Testing nodejs →