Review feedback: docs and nits

lib/Normalize_std_ast.ml

@@ -12,6 +12,22 @@
 open Parser_standard
 open Std_ast
 
+(* CR jane-syntax: Soon we will import the PR eliminating the rest of the
+   attribute-based jane syntax mechanism
+   (https://github.com/ocaml-flambda/flambda-backend/pull/3162), and the
+   person who does that will have some work to do in this file.
+
+   Currently, this file doesn't explicitly handle much of what remains in
+   jane syntax (e.g., immutable arrays and module strengthening). But it is
+   surprising that it doesn't - it must be the case that these features are
+   undertested or the obvious normalization problems they create when erasing
+   jane syntax are masked by the broken round-trip check.
+
+   To fix that, it will likely be necessary to add explicit normalization
+   logic for the remaining jane street extensions to this file. At the same
+   time, [is_erasable_jane_syntax] below, which is currently just handling
+   [curry] attributes, should probably be inlined or renamed. *)
+
 let is_doc = function
   | {attr_name= {Location.txt= "ocaml.doc" | "ocaml.text"; _}; _} -> true
   | _ -> false

vendor/parser-extended/parse.ml

@@ -175,7 +175,7 @@ let prepare_error err =
         | Constrained_types ->
             Format.fprintf ppf "constrained types are not supported"
         | Private_types ->
-            Format.fprintf ppf  "private types are not supported"
+            Format.fprintf ppf "private types are not supported"
         | Not_with_type ->
             Format.fprintf ppf "only %s constraints are supported"
               "with type t ="

vendor/parser-jane/README.md

@@ -13,7 +13,14 @@ Just run:
 ./parser-jane/repatch.sh {path-to-flambda-backend}
 ```
 Additional steps may be necessary if you are adding or removing files - see the
-top-level HACKING.jst.md
+top-level HACKING.jst.md.
+
+Note: The import script tries to apply a patch to the newly imported parser that
+restores the changes needed by ocamlformat. This diff may fail to apply cleanly,
+for example if the same parts of the parser have changed in flambda-backend.
+In that case, you will see in the script's output that some parts of the patch
+haven't been applied and it will create ".rej" files describing them. You must
+manually look at and apply these rejected portions.
 
 ### Manually