Great article. As someone new to Swift and SwiftUI, the lack of official documentation around these function builders is frustrating. The best I could find was a draft proposal [1].
Well I think that's because they aren't yet an official part of the language until that proposal is accepted, and Apple is shipping them as a custom extension to Swift that they hope to remove at some point.
Edit: Also the current version of the proposal is here: https://github.com/apple/swift-evolution/blob/master/proposa...