Learning Rust by doodling around with Nannou. Starting Point Schotter Repo
I first forgot to add adding 'resolver=2' to the top level Cargo.toml. I hadn't needed it for other nannou projects, so why do I need it here? In the other projects I didn't have a workspace. So instead I had written 'edition = "2021"' in my Cargo.toml.
According to The Edition Guide edition = "2021" implies resolver = "2" in Cargo.toml.