Remove dependency on rresult. (#306)

Author: dbuenzli

odoc.opam

@@ -25,7 +25,6 @@ depends: [
   "fpath" {build}
   "ocaml" {>= "4.02.0"}
   "result" {build}
-  "rresult" {build & >= "0.3.0"}
   "tyxml" {build & >= "4.3.0"}
 
   "alcotest" {dev & >= "0.8.3"}

src/odoc/fs.mli

@@ -59,7 +59,7 @@ module File : sig
   val of_string : string -> t
   val to_string : t -> string
 
-  val read : t -> (string, [> Rresult.R.msg ]) result
+  val read : t -> (string, [> `Msg of string ]) result
 
   module Table : Hashtbl.S with type key = t
 end

src/parser/dune

@@ -4,5 +4,5 @@
  (name odoc__parser)
  (public_name odoc.parser)
  (preprocess (pps bisect_ppx -conditional))
- (libraries astring odoc__alias odoc__compat odoc__model rresult)
+ (libraries astring odoc__alias odoc__compat odoc__model)
  (flags (:standard -open Odoc__alias)))

src/parser/reference.ml

@@ -364,11 +364,15 @@ let read_path_longident location s =
   | Some r -> Result.Ok r
   | None -> Result.Error (Parse_error.expected "a valid path" location)
 
-let read_mod_longident warnings location lid : (Paths.Reference.Module.t, Error.t) Result.result =
-  let (>>=) = Rresult.(>>=) in
-
-  parse warnings location lid >>= function
-  | `Root (_, (`TUnknown | `TModule))
-  | `Dot (_, _)
-  | `Module (_, _) as r -> Result.Ok r
-  | _ -> Result.Error (Parse_error.expected "a reference to a module" location)
+let read_mod_longident
+    warnings location lid : (Paths.Reference.Module.t, Error.t) Result.result
+  =
+  match parse warnings location lid with
+  | Error _ as e -> e
+  | Ok p ->
+      match p with
+      | `Root (_, (`TUnknown | `TModule))
+      | `Dot (_, _)
+      | `Module (_, _) as r -> Result.Ok r
+      | _ ->
+          Result.Error (Parse_error.expected "a reference to a module" location)

src/parser/syntax.ml

@@ -770,13 +770,14 @@ let rec block_element_list
                  cooperation to get the real location. *)
               let r_location =
                 Location.nudge_start (String.length "@canonical ") location in
-
-              let (>>=) = Rresult.(>>=) in
-              let result =
-                Reference.read_path_longident r_location s >>= fun path ->
-                Reference.read_mod_longident
-                  input.warnings r_location s >>= fun module_ ->
-                Result.Ok (`Canonical (path, module_))
+              let result = match Reference.read_path_longident r_location s with
+              | Error _ as e -> e
+              | Ok path ->
+                  match
+                    Reference.read_mod_longident input.warnings r_location s
+                  with
+                  | Error _ as e -> e
+                  | Ok module_ ->  Result.Ok (`Canonical (path, module_))
               in
               match result with
               | Result.Ok _ as result -> result