ref: 2a3b64a5642729ab3bf83a21ea6bf59fc2a88f2c
dir: /test/occur.myr/
use std /* checks that f is not an infinite type (ie, the type doesn't exist within itself). If 'f' typechecked, it's type would be: f : (-> (-> (-> ... ad infinitum ...))) */ const f = { -> f }