A typeful interface for calling Elisp, as external does for C. E.g.,
module F = struct
let not : bool -> bool = Q.not <: bool @-> return bool
let about_emacs : unit -> unit = Q.about_emacs <: nullary @-> return nil
end
let non f = Fn.compose F.not f
let about_emacs = F.about_emacs
The F convention is borrowed from the Emacs C source.
val return : 'a Ecaml.Value.Type.t ‑> 'a tval nil : unit Ecaml.Value.Type.tval nullary : unit Ecaml.Value.Type.tval (<:) : Ecaml.Symbol.t ‑> 'a t ‑> 'aQ.foo <: ... types an Elisp function, like how foo :> t types an OCaml value.
val (@->) : 'a Ecaml.Value.Type.t ‑> 'b t ‑> ('a ‑> 'b) t