NodeJS harmony gives SyntaxError on import

Question

I was testing node with ES6 with the flag child_process --harmony but it fails at first step when I import. Any ideas?

import {'spawn'} from child_process;
console.log(spawn);

And i run:

node --harmony test.js

And I get:

:1
(function (exports, require, module, __filename, __dirname) { import {spawn} f
                                                              ^^^^^^
SyntaxError: Unexpected token import

Unrelated, but why are you importing the string "spawn" from an identifier called `child_process`? — Rick, Jun 05 '14 at 22:37

barry-johnson · Answer 1 · 2015-12-08T21:09:31.713

6

Not all features of ES6 are supported in v8 and thus in Node. Modules I believe are one of those things.

You might find this compatibility matrix handy: http://kangax.github.io/es5-compat-table/es6/

You could use the Traceur compiler to do this, although not everything is implemented with modules yet it appears

Edit in Dec 2015 - as some comments to this answer suggest, at this point, Babel has become the preferred ES6 transpiler. At the time I wrote my original answer, Babel was still known as 6to5 and was not as popular as Traceur. Today, Babel is the go-to choice.

edited Dec 08 '15 at 21:09

answered Apr 14 '14 at 21:47

barry-johnson

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you can use `babel` package from npm – langpavel Feb 19 '15 at 15:12
2

To get almost full compatibility with the ES6 standard you can install babel-node ```npm install -g babel-node``` and then run your code with babel-node. Here's [a link](https://babeljs.io/docs/setup/) in case this information becomes outdated. – Rakan Nimer Aug 05 '15 at 15:03
1

**Important**: the package name is `babel-cli`, **NOT** `babel-node`. – Jebediah Nov 01 '18 at 20:57

score 0 · Answer 2 · answered Jan 16 '20 at 17:04

Try the --experimental-modules flag

Back in 2017, Node.js 8.9.0 shipped experimental support for ECMAScript modules, known for their import and export statements. This support was behind the flag --experimental-modules.

https://medium.com/@nodejs/announcing-a-new-experimental-modules-1be8d2d6c2ff

NodeJS harmony gives SyntaxError on import

2 Answers2