import from, export class

[Shin1gami]

Let's say we want to usea module with class like:

export class Test {
    constructor() {
    }
}

And load it:

import {test} from 'test.js';
new Test();

But when we try to run it:

iojs --use_strict --harmony --es_staging server.js

We've got an error:

export class Test {
^^^^^^
SyntaxError: Unexpected reserved word
    at exports.runInThisContext (vm.js:53:16)
    at Module._compile (module.js:427:25)
    at Object.Module._extensions..js (module.js:462:10)
    at Module.load (module.js:339:32)
    at Function.Module._load (module.js:294:12)
    at Module.require (module.js:349:17)
    at require (module.js:368:17)
    at Object.<anonymous> (server.js:4:1)
    at Module._compile (module.js:444:26)
    at Object.Module._extensions..js (module.js:462:10)

So, can we use such syntax?

[bnoordhuis]

Not at the moment, the ES6 module system in V8 is still in its infancy. Your example can probably be made to parse by passing --harmony_modules on the command line but I won't vouch for it actually working.

[JiangJie]

@bnoordhuis It appears that --harmony_modules is still not working at iojs v2.2.0.

import {param} from '../config/param';
^^^^^^
SyntaxError: Unexpected token import

[navaru]

Is there a plan to implement the ES6 module syntax when V8 provides support?

A lot of module authors have begun to write modules with ES6 syntax, adding a special build process to enable a package to be used in io.js / node adds complexity and segmentation in usability, it feels like the whole CoffeeScript-ish era again 😄.

[bnoordhuis]

@teugen There's been some discussion about that here: nodejs/NG#5

[MadLittleMods]

👍

Running into the reserved word SyntaxError in iojs v2.3.3 even with the --harmony_modules flag.

---

An easy solution for now is to use babel-tape-runner or for single files, 6to5, and either can be used nicely in a script in package.json:

npm run execute-script

{
  "scripts": {
    "execute-script": "babel-tape-runner index.js || exit 0"
  }
}

// ...
"scripts": {
    "execute-script": "6to5 src/index.js | iojs"
},

[trevnorris]

I'm fairly certain that iojs will need to hook into V8 to specify how to resolve the module path. This has not been done, and don't think the hooks exist yet.

[cirano-eusebi]

@MadLittleMods I tryed what you said but kept having the same error...

Is there something wrong in the declarations that I'm doing?

/*CliParser.js*/

export class CliParser {

   static parse(arguments) {
   //Code goes here
   }
}

/*index.js*/

import {CliParser} from './CliParser.js';

//Parse the argument vector
var parsedArguments = CliParser.parse(process.argv);

I've done as you said and added a script in my package.json file:

/*package.json*/

"scripts": {
    "IPtoNode" : "6to5 index.js | iojs",
    "test": "echo \"Error: no test specified\" && exit 1"
},

This is what i get when i run the script.

#console

npm run IPtoNode 
PathToApp\IPtoNode\CliParser.js:1
(function (exports, require, module, __filename, __dirname) { export class Cli
                                                              ^^^^^^
SyntaxError: Unexpected reserved word
    at exports.runInThisContext (vm.js:53:16)
    at Module._compile (module.js:413:25)
    at Object.Module._extensions..js (module.js:448:10)
    at Module.load (module.js:355:32)
    at Function.Module._load (module.js:310:12)
    at Module.require (module.js:365:17)
    at require (module.js:384:17)
    at [stdin]:12:17
    at Object.exports.runInThisContext (vm.js:54:17)
    at Object.<anonymous> ([stdin]-wrapper:6:22)

Note that if I run it out of the npm script it also produces the same error.

[trevnorris]

The V8 API does not exist to allow us to define what happens with the path passed to import, so V8 has no idea how to resolve where the module is you're requesting.

[MadLittleMods]

@MagoDopado It is the because the dependency, CliParser.js, is not getting transpiled by babel. You can use babel-tape-runner

npm run execute-script

{
  "scripts": {
    "execute-script": "babel-tape-runner index.js || exit 0"
  }
}

[Teomazivila]

Hi Everyone, I have an issue that is related to this topic. I am creating a an ASPNETCORE Angular app, and getting the bellow error when executing DOTNET WATCH RUN
[error] D:\TeoProjects.Net\AspNet\Teomaz_C\ClientApp\node_modules\bluebird\js\release\reduce.js:1
(function (exports, require, module, __filename, __dirname) {

SyntaxError: Invalid or unexpected token
at new Script (vm.js:80:7)
at createScript (vm.js:274:10)
at Object.runInThisContext (vm.js:326:10)
at Module._compile (internal/modules/cjs/loader.js:664:28)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:712:10)
at Module.load (internal/modules/cjs/loader.js:600:32)
at tryModuleLoad (internal/modules/cjs/loader.js:539:12)
at Function.Module._load (internal/modules/cjs/loader.js:531:3)
at Module.require (internal/modules/cjs/loader.js:637:17)
at require (internal/modules/cjs/helpers.js:22:18)
at module.exports (D:\TeoProjects.Net\AspNet\Teomaz_C\ClientApp\node_modules\bluebird\js\release\promise.js:788:1)
at Object. (D:\TeoProjects.Net\AspNet\Teomaz_C\ClientApp\node_modules\bluebird\js\release\bluebird.js:9:36)
at Module._compile (internal/modules/cjs/loader.js:701:30)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:712:10)
at Module.load (internal/modules/cjs/loader.js:600:32)
at tryModuleLoad (internal/modules/cjs/loader.js:539:12)

I have tried:

1. npm install
2. Deleting the node_modules and and reinstalling them again
   I tried a couple more options that I can't remember that were suggested on Stackoverflow.
   I am quite new on this topic, so please take it easy on me. Thanks in advanced