ref: fb7dd4b3a868cb8987049c95bb32e6425a73c8b9
dir: /module/lock.m/
Lock: module { PATH: con "/dis/lib/lock.dis"; Semaphore: adt { c: chan of int; obtain: fn(nil: self ref Semaphore); release: fn(nil: self ref Semaphore); new: fn(): ref Semaphore; }; init: fn(); };