Client values requiring monomorphism

I'm new to Eliom and encounter The types of client values must be monomorphic from its usage or from its type annotation. This is the example I've got so far:

  let%server new_entry_form =
  let open Html.D in
  let field = Raw.input ~a:[a_input_type `Text] () in
  let submit = Raw.button ~a:[a_class ["button"]] [txt "add"] in
  ignore
  [%client
  let open Html.D in
  let open Js_of_ocaml_lwt.Lwt_js_events in
  let field = Html.To_dom.of_input ~%field in
  (Lwt.async @@ fun() ->
  clicks (Html.To_dom.of_element ~%submit)
  (fun _ _ ->
  let entered = field##value |> Js_of_ocaml.Js.to_string in
  add_entry {id="5";name=entered;description=""};
  Lwt.return_unit):unit
  )];

  div [
  field;submit
  ]

I'm guessing ~%field and ~%submit are the trouble. Why does this produce an error when it looks much like the tutorial code? Where have I gone wrong?

The conversation continues 2

Follow the reasoning

fen_ko6 Sept Permalink
An annotation on the client value resolves it:
```
  let _ : unit Lwt.t Eliom_client_value.t = [%client ...] in
```
After that, access the value attribute rather than a method that doesn't exist:
```
  let entered = field##.value |> Js_of_ocaml.Js.to_string in
```
Hope that's useful!
tam_ly7 Sept Permalink
Many thanks! It works now.

Client values requiring monomorphism

The conversation continues 2

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