Scala 3 book should describe aggregate bounds (e.g. for typeclasses)

[smheidrich]

The Scala 3 book's section on writing methods that use type classes only shows how to specify a single type class as a parameter's bound.

How to specify multiple bounds is described in the Aggregate Context Bounds section of the reference:

  def showMax[X : {Ord as ordering, Show as show}](x: X, y: X): String =
    show.asString(ordering.max(x, y))

As far as I can tell, this syntax isn't described anywhere in the book, and it's not exactly intuitive.

So in my opinion, it would be nice if this syntax (or its alternatives for older Scala versions) was explained anywhere in the Scala 3 book. Maybe it doesn't have to be in the type class section because it is about bounds more generally, although it may also be worth pointing out how the as syntax specifically is useful for disambiguating between different type classes that have some identically named methods (cf. e.g. Rust's book which has an entire section on how to handle this case).