ref: 207d86eced0726bf8ce0eaeb6b6e06a40e47a2d9 dir: /libstd/try.myr/
use "option.use" use "fmt.use" pkg std = generic try : (v : option(@a) -> @a) ;; generic try = {v match v | `Some x: -> x | `None: fatal(1, "expected `Some @a, got `None\n") ;; }