Hello, Perhaps I'm overlooking something but replacing include BI with include (BI : B with type t := t) seems like a reasonable fix to me. Danny -- Caml-list mailing list. Subscription management and archives: https://sympa.inria.fr/sympa/arc/caml-list https://inbox.ocaml.org/caml-list Forum: https://discuss.ocaml.org/ Bug reports: http://caml.inria.fr/bin/caml-bugs