javascript - Passing getChildContext() to reactjs higher order components throws unexpected token error in webpack -

i got following example here make higher order component passing context reliably.

however, there unexpected token error passing getchildcontext() function when compiling script using webpack:

getchildcontext = () => getchildcontext(this.props);                ^^^ 

code:

const providecontext =    (childcontexttypes, getchildcontext) => (component) => {     class contextprovider extends react.component {       getchildcontext = () => getchildcontext(this.props);        render() {         return <component {...this.props} />;       }     }     contextprovide.childcontexttypes = childcontexttypes;      return contextprovider;   }; 

is there workaround way of passing function?

my webpack config:

var common = {     output: {path: build_dir},     module: {         loaders: [             {                 test: /\.js$/,                 loader: 'babel',                 include: app_dir,                 query: {                     presets: ['es2015', 'react']                 }             },             {                 test: /\.css$/,                 loader: "style-loader!css-loader"             },             {                 test: /\.(png|woff|woff2|eot|ttf|svg)$/,                 loader: 'url-loader?limit=100000'             },             {                 test: /\.(png|jpg)$/,                 loader: 'file-loader'             }         ]     },     resolve: {         alias: {             'react': path.join(__dirname, 'node_modules', 'react'),             'react-dom': path.join(__dirname, 'node_modules', 'react-dom')         },         extensions: ['', '.js']     },  };   config.push(     merge(common, {         entry: {             itempage:app_dir+'/page/'+filename+'.js',          },         devtool: 'source-map',         output: {             filename: "[name].js",             librarytarget: 'umd',             library: "[name]"         },         externals: [{             react: {                 root: 'react',                 commonjs2: 'react',                 commonjs: 'react',                 amd: 'react',              },             "react-dom": "reactdom"         }]      }) );  module.exports = config; 

you getting unexpected token because missing 1 babel plugin, transform-class-properties included in stage-1 preset

with stage-1, works

without stage-1, not work

so in order fix it, have to

1º install stage-1

npm install --save-dev babel-preset-stage-1 

2º add .babelrc

{   "presets": ["react","es2015","stage-1"] } 

or webpack config

query: {        presets: ["react","es2015","stage-1"] }