ref: 563d4d25dd8386f6597a6ad636aa0886ab2032df dir: /lib/thread/ncpu+plan9.myr/
use std pkg thread = const ncpu : (-> int) ;; const ncpu = { match std.intparse(std.getenvv("NPROC", "")) | `std.Some n: -> n | `std.None: -> 1 ;; }