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module List = ListLabels
module Option = struct
let map t ~f =
match t with
| None -> None
| Some x -> Some (f x)
;;
end
module Json = struct
type t = Yojson.Safe.t
exception Of_json of (string * t)
let () =
Printexc.register_printer (function
| Of_json (msg, _) -> Some ("Jsonrpc: json conversion failed: " ^ msg)
| _ -> None)
;;
let error msg json = raise (Of_json (msg, json))
module Jsonable = struct
module type S = sig
type json
type t
val yojson_of_t : t -> json
val t_of_yojson : json -> t
end
with type json := t
end
let field fields name conv = List.assoc_opt name fields |> Option.map ~f:conv
let field_exn fields name conv =
match field fields name conv with
| Some f -> f
| None -> error ("missing field " ^ name) (`Assoc fields)
;;
module Conv = struct
let string_of_yojson = function
| `String s -> s
| json -> error "expected string" json
;;
end
end