如何解决webpack 2错误，模块构建失败：SyntaxError ,,？

Question

I cloned this reactjs/webpack2 repo:

https://github.com/ModusCreateOrg/budgeting-sample-app

which is working great , but I was playing around and chaned the index.js file with some properties/spread:

 let myprops = [1,2];
 let copyprops = {...myprops};

When I run npm start I get a build error:

Module build failed: SyntaxError: .../index.js:Unexpected token

It is referring to the line with the spread operator, how can I fix this? see also: repo

Answer 1

If you haven't changed the presets that are included in that repo then the spread operator won't work as you're noticing.

The spread operator is actually a part of the stage2 preset. You can find more info on that here https://github.com/babel/babel-loader/issues/170

So in order for your code to work you'll need to make sure you've both installed the babel-preset-stage-2 and set it as a preset in your .babelrc

https://www.npmjs.com/package/babel-preset-stage-2

Answer 2

well , i would do `

class App extends Component {
render() {
    let myprops = [1,2];
    let [...a] = myprops;

    return (
        <div className="viewport">

        </div>
    );
}

}

just for quick solution.`Reference here . thanks