I am playing with the brand new Apple Augmented Reality by Tutorials: Complete Book Now Available!
In chapter one I get this error
TinyToyTank/ViewController.swift:60:21: Value of type ‘TinyToyTank._TinyToyTank’ has no member ‘turret’
Not sure maybe the Reality Composer project file TinyToyTank.rcproject has issues in it? I picked it from github.