ref: 4ca93982fdef1ddb426b5595f814f3099adfdc65
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("expected `Some @a, got `None\n")
;;
}