ref: 60964cf8e347043da18a3f79217e5f5fa3a8bb5e dir: /lib/thread/ncpu+plan9.myr/
use std pkg thread = const ncpu : (-> int) ;; const ncpu = { match std.intparse(std.getenvv("NPROC", "1")) | `std.Some n: -> n | `std.None: -> 1 ;; }