ref: e559a7dc5f76558ea0f56d9bf26385b04b496bd4
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 }