exported function vs object for webpack.config.js

[jraller]

In section 4.3 the following code is shown:

module.exports = (env) => {
  if (env === 'production') {
    return merge(commonConfig, productionConfig);
  }
  return merge(commonConfig, developmentConfig);
}

but this changes things so that a function is exported rather than an object. In order to utilize the webpack.config.js file with other tools it was pointed out to me that I needed to call what I had required in in order to get the function. Alternatively changing the code to

module.exports = ((env) => {
  if (env === 'production') {
    return merge(commonConfig, productionConfig);
  }
  return merge(commonConfig, developmentConfig);
})();

would retain the expected behavior for the webpack.config.js file by turning it into an function expression instead of a function definition.

[bebraw]

What other tools do you have in mind? Where are you planning to use the configuration?

If you follow the book convention, then the invocation pattern is like this:

const config = require('./webpack.config')(env); // Pass env now

[sapegin]

In that case env would be undefined. Which other tools you mean? For example in React Styleguidist we support the fist variant.

[jraller]

@sapegin makes a really good point about env being undefined and it appears not just when the file is required, I set up the interior of my function with a switch on env, but added a default that exports my test configuration.

The tool I'm using it with is WallabyJS https://wallabyjs.com/