This error appeared after I added the react-hot
loader in an array following this tutorial: https://thoughtbot.com/blog/setting-up-webpack-for-react-and-hot-module-
It seems that the query is an alternative way of customizing the behaviour of a single loader, that is cleaner than specifying those parameters inline (see below). If multiple loaders are present, Webpack does not know to which the query
configuration applies.
The following should solve your problem:
module: {
loaders: [{
test: /\.jsx?$/,
exclude: /node_modules/,
loaders: ['react-hot', 'babel?presets[]=es2015,presets[]=stage-0,presets[]=react,plugins[]=transform-runtime']
}
EDIT: While this solution works for Webpack 1, see the other answers for cleaner solutions that work in more recent versions.