type 'a t
val _Promise : 'aval _catch : 'a t Js_of_ocaml.Js.t -> ('b -> 'a t Js_of_ocaml.Js.t) -> 'a t Js_of_ocaml.Js.tval _then : 'a t Js_of_ocaml.Js.t -> ?catch:('c -> 'b t Js_of_ocaml.Js.t) -> ('a -> 'b t Js_of_ocaml.Js.t) -> 'b t Js_of_ocaml.Js.tval resolve_value : 'a -> 'a t Js_of_ocaml.Js.tval resolve_promise : 'a t Js_of_ocaml.Js.t -> 'a t Js_of_ocaml.Js.tval reject_value : 'a -> 'a t Js_of_ocaml.Js.tval reject_promise : 'a t Js_of_ocaml.Js.t -> 'a t Js_of_ocaml.Js.tval race : 'a t Js_of_ocaml.Js.t Js_of_ocaml.Js.js_array Js_of_ocaml.Js.t -> 'a t Js_of_ocaml.Js.tval all : 'a t Js_of_ocaml.Js.t Js_of_ocaml.Js.js_array Js_of_ocaml.Js.t -> 'a t Js_of_ocaml.Js.t