I am currently learning the Nextjs framework. I would say I have a solid grasp of the concepts already, but there are still a few things I am not sure about. One of those things is the spread operator [...var] or [[...var]] in a dynamic page | route file name.
For example this line from next/auth docs:
pages/api/auth/[...nextauth].js
Is there some concrete use case (that can't be achieved using getStaticPaths()), or is it just a naming convention which I don't know about?