Node.js Exporting and Importing Module in node.js Using Imports In ES6
Example
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Currently ES6 supports import statements natively Refer here
So if we have a file called fun.js…
export default function say(what){
console.log(what);
}
export function sayLoud(whoot) {
say(whoot.toUpperCase());
}
…and if there was another file named app.js where we want to put our previously defined functions to use, there are three ways how to import them.
Import default
import say from './fun';
say('Hello Stack Overflow!!'); // Output: Hello Stack Overflow!!
Imports the say() function because it is marked as the default export in the source file (export default …)
Named imports
import { sayLoud } from './fun';
sayLoud('JS modules are awesome.'); // Output: JS MODULES ARE AWESOME.
Named imports allow us to import exactly the parts of a module we actually need. We do this by explicitly naming them. In our case by naming sayLoud in curly brackets within the import statement.
Bundled import
import * as i from './fun';
i.say('What?'); // Output: What?
i.sayLoud('Whoot!'); // Output: WHOOT!
If we want to have it all, this is the way to go. By using the syntax * as i we have the import statement provide us with an object i that holds all exports of our fun module as correspondingly named properties.
Paths
Keep in mind that you have to explicitly mark your import paths as relative paths even if the file to be imported resided in the same directory like the file you are importing into by using ./. Imports from unprefixed paths like
import express from 'express';
will be looked up in the local and global node_modules folders and will throw an error if no matching modules are found.
