Compose components with slots in Svelte 3
When creating an app out of components we tend to compose them inside of one another. Svelte allows us to create slots using a
<slot /> component so the components we create can accept any children and render those.
In this lesson we are going to see an example of a slot being used to create a generic
box component which can accept any children as a prop, along with handling a case where no children were provided.