Default export
Learn to export a module's default value.
Default export
A module's default export is its main value. A module can have at most one default export.
You can write a function or class directly as the default:
export default function greet(name) {
return "Hello " + name;
}When importing you skip the curly braces; you pick the name yourself.
Anonymous default
A default export can also be an anonymous function. This is common in libraries.
export default function () {
return "Ready";
}You can also export a previously declared value as the default:
function greet() { return "Hello"; }
export default greet;In both cases the importing side picks a name.
Exercise Write a default export
Export a function called greet as the default. It takes a name parameter and returns "Hello " + name.
Show example solution
Write export default function greet(name) and return a string.
Example solution:
export default function greet(name) {
return "Hello " + name;
}Test yourself
-
How many default exports can a module have?
- Unlimited
- At most five
- Exactly one
- Modules have no default
Show answer
Exactly one — Correct! A module has exactly one default export.
-
Return a greeting
export default function greet() { return ____; }Show answer
export default function greet() { return "Hello"; } -
Default export concepts
- export default
- module's main value
- one per module
- single default
- default import
- no name needed
- anonymous function
- can be default
-
Export a declared function as default
export default ____; function greet(name) { return "Hello " + name; }Show answer
export default greet; function greet(name) { return "Hello " + name; }