If you’re knee-deep in the JavaScript world, you’ve probably stumbled upon the terms “export default” and “named exports.”
They might sound like mysterious incantations to the uninitiated, but fear not!
Let’s break down these concepts, so you can wield them like a JavaScript wizard.
Export Default:
Imagine you have a JavaScript file full of functions, objects, or a single value that you want to share with the world.
You don’t want to clutter things up with a bunch of names; you just want to say, “This right here is the main thing, the star of the show.”
Enter export default. It's like putting a giant spotlight on one particular thing in your file.
When another file imports from this module, it gets that one special thing by default. No need to know its name—just grab it and go.
// File: superhero.js
const superpower = 'Flying';
export default superpower;
In another file:
// File: main.js
import specialAbility from './superhero.js';
console.log(specialAbility); // Output: 'Flying'
Easy, right?
You import the default export without caring about the name.
Named Exports:
Now, what if you have a bunch of cool stuff in your file — multiple functions, variables, or objects?
You want to share the spotlight, give each of them a chance to shine. This is where named exports come in handy.
You explicitly declare what you want to share by putting export in front of each item, giving them a name.
It's like assembling an ensemble cast for your JavaScript module.
// File: team.js
export const leader = 'Captain';
export const sidekick = 'Robin';
export const mascot = 'Duck';
// You can also do this in a more concise way:
export { leader, sidekick, mascot };
In another file:
// File: main.js
import { leader, sidekick } from './team.js';
console.log(leader, sidekick); // Output: 'Captain Robin'
You import only what you need, and you know exactly which items you’re getting.
No surprises, no guesswork — just the actors you cast for your JavaScript play.
When to Use Which?
So, when should you use export default and when should you go for named exports? It depends on your script's narrative:
- Export Default: Use this when you have a clear protagonist in your file, a single main thing that steals the spotlight. It’s simple and straightforward.
- Named Exports: Employ this when your file is a team effort, with various functions, variables, or objects playing crucial roles. It’s your go-to choice for sharing the stage.
Mixing It Up: Combining Default and Named Exports
You can mix default and named exports in the same file.
It’s like having a cake with a variety of toppings — the secret ingredient is there, and you also have a selection of named exports.
// bakery.js
const secretIngredient = "Magical sprinkles";
const topping1 = "Chocolate chips";
const topping2 = "Rainbow sprinkles";
export { topping1, topping2 };
export default secretIngredient;
When you import from bakery.js, you can get the default and named exports together:
// kitchen.js
import magicIngredient, { topping1, topping2 } from './bakery.js';
console.log(magicIngredient); // Output: Magical sprinkles
console.log(topping1); // Output: Chocolate chips
console.log(topping2); // Output: Rainbow sprinkles
Recap
In the grand play that is JavaScript, export default is your lone hero, basking in the limelight.
Named exports, on the other hand, form your versatile ensemble cast, each member playing a unique role.
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