It gives a read-only peek at the scope of the imported module. import {foo} from 'bar.js'; // you can't re-bind `foo` from here, but if // a functi

It gives a read-only peek at the scope of the imported module. import {foo} from 'bar.js'; // you can't re-bind `foo` from here, but if // a function defined in 'bar.js' mutates it, // the change is reflected here too. It enables circular dependencies, for free, and makes it easy to discard unused code. See the examples at the Rollup playground. http://rollupjs.org http://rollupjs.org