JavaScript export / import doesn't work

Question

it might be a silly question but I can't fix it anyway. I have a JavaScript file with various functions I'd like to export.

export function AddNumbers(...numbers)
{
    let value = 0;

    for(var i = 0;i < numbers.length;i++)
    {
        value += numbers[i];
    }

    return value;
}  

When I call this method (using mocha) I get an error message "export function AddNumbers(...numbers) Unexpected token export". The project is build as ES6. Does anybody know what I'm doing wrong?

Best regards, Torsten

Answer 1

You need to use module.exports as NodeJS uses CommonJS Module syntax which requires to use module.exports and not just export which is defined by ES6 module syntax. So, make sure CommonJS is also configured properly in your project.

Answer 2

Another solution is to use Babel. Install it with

npm install babel-core --save-dev
npm install babel-preset-es2015 --save-dev

Create in root directory a file .babelrc with following content

{
    "preset" : ["es2015"]
}

and finally change the script in package.json to run into:

"scripts": {
    "test": "mocha Tests --require babel-core/register"
}

and now export / import works.