Node.js - SyntaxError: Unexpected token import

I don't understand what is wrong. Node v5.6.0 NPM v3.10.6

The code:

function (exports, require, module, __filename, __dirname) {
    import express from 'express'
};

The error:

SyntaxError: Unexpected token import
    at exports.runInThisContext (vm.js:53:16)
    at Module._compile (module.js:387:25)
    at Object.Module._extensions..js (module.js:422:10)
    at Module.load (module.js:357:32)
    at Function.Module._load (module.js:314:12)
    at Function.Module.runMain (module.js:447:10)
    at startup (node.js:140:18)
    at node.js:1001:3

Node 13+ Since Node 13, you can use either the .mjs extension, or set {"type": "module"} in your package.json. You don't need to use the --experimental-modules flag. Modules is now marked as stable in node.js

Node 12 Since Node 12, you can use either the .mjs extension, or set "type": "module" in your package.json. And you need to run node with the --experimental-modules flag.

Node 9 In Node 9, it is enabled behind a flag, and uses the .mjs extension.

node --experimental-modules my-app.mjs

While import is indeed part of ES6, ~~it is unfortunately not yet supported in NodeJS by default, and has only very recently landed support in browsers.~~

See browser compat table on MDN and this Node issue.

From James M Snell's Update on ES6 Modules in Node.js (February 2017):

Work is in progress but it is going to take some time — We’re currently looking at around a year at least.

Until support shows up natively (now marked stable in Node 13+), ~~you'll have to continue using classic require statements~~:

const express = require("express");

If you really want to use new ES6/7 features in NodeJS, you can compile it using Babel. Here's an example server.

Unfortunately, Node.js doesn't support ES6's import yet.

To accomplish what you're trying to do (import the Express module), this code should suffice

var express = require("express");

Also, be sure you have Express installed by running

$ npm install express

See the Node.js Docs for more information about learning Node.js.

I'm shocked esm hasn't been mentioned. This small, but mighty package allows you to use either import or require.

Install esm in your project

$ npm install --save esm

Update your Node Start Script to use esm

node -r esm app.js

esm just works. I wasted a TON of time with .mjs and --experimental-modules only to find out a .mjs file cannot import a file that uses require or module.exports. This was a huge problem, whereas esm allows you to mix and match and it just figures it out... esm just works.

Node.js - SyntaxError: Unexpected token import

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