The following code is a minimized version of camlworks/dream#297 that no longer calls into Dream at all:
type _ Effect.t += E : unit Effect.t
let () =
Effect.Deep.try_with
begin fun () ->
Lwt_main.run begin
Lwt.bind (Lwt_unix.sleep 1.) @@ fun () ->
Effect.perform E;
assert false
end
end
()
{
effc = fun (type a) (e : a Effect.t) ->
match e with
| E ->
Option.some @@ fun (k : (a, _) Effect.Deep.continuation) ->
prerr_endline "handling E";
Effect.Deep.continue k ()
| _ -> None
}Running this on OCaml 5.1.0 with Lwt 5.7.0 results in
Fatal error: exception Stdlib.Effect.Unhandled(Dune__exe__Json.E)
Replacing Lwt_unix.sleep 1. by, say, Lwt.pause () results in
handling E
Fatal error: exception File "dream/example/e-json/json.ml", line 9, characters 8-14: Assertion failed
which is the correct output, and what I would expect in both cases.
The following code is a minimized version of camlworks/dream#297 that no longer calls into Dream at all:
Running this on OCaml 5.1.0 with Lwt 5.7.0 results in
Replacing
Lwt_unix.sleep 1.by, say,Lwt.pause ()results inwhich is the correct output, and what I would expect in both cases.