CCThreadstatus: unstable
val spawn : ( unit -> _ ) -> tspawn f creates a new thread that runs f ().
val spawn1 : ( 'a -> _ ) -> 'a -> tspawn1 f x is like spawn (fun () -> f x).
val spawn2 : ( 'a -> 'b -> _ ) -> 'a -> 'b -> tspawn2 f x y is like spawn (fun () -> f x y).
module Arr : sig ... endmodule Barrier : sig ... end