refactor: scopes in refmt command (#2836)

src/refmt/refmt.ml

@@ -1,9 +1,8 @@
-(*
- * Copyright (c) 2015-present, Facebook, Inc.
+(* Copyright (c) 2015-present, Facebook, Inc.
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *)
+*)
 
 module Cmdliner = Vendored_cmdliner
 open Cmdliner
@@ -105,99 +104,101 @@ let refmt
     (* FIXME: Reason_syntax_util.report_error Format.err_formatter exn; *)
     exit 1
 
-let split_lines s =
-  let rec loop ~last_is_cr ~acc i j =
-    if j = String.length s
-    then
-      let acc =
-        if j = i || (j = i + 1 && last_is_cr)
-        then acc
-        else String.sub s i (j - i) :: acc
+let () =
+  let examples =
+    let split_lines s =
+      let rec loop ~last_is_cr ~acc i j =
+        if j = String.length s
+        then
+          let acc =
+            if j = i || (j = i + 1 && last_is_cr)
+            then acc
+            else String.sub s i (j - i) :: acc
+          in
+          List.rev acc
+        else
+          match s.[j] with
+          | '\r' -> loop ~last_is_cr:true ~acc i (j + 1)
+          | '\n' ->
+            let line =
+              let len = if last_is_cr then j - i - 1 else j - i in
+              String.sub s i len
+            in
+            loop ~acc:(line :: acc) (j + 1) (j + 1) ~last_is_cr:false
+          | _ -> loop ~acc i (j + 1) ~last_is_cr:false
       in
-      List.rev acc
-    else
-      match s.[j] with
-      | '\r' -> loop ~last_is_cr:true ~acc i (j + 1)
-      | '\n' ->
-        let line =
-          let len = if last_is_cr then j - i - 1 else j - i in
-          String.sub s i len
+      loop ~acc:[] 0 0 ~last_is_cr:false
+    in
+    let[@tail_mod_cons] rec concat_map f = function
+      | [] -> []
+      | x :: xs -> prepend_concat_map (f x) f xs
+    and[@tail_mod_cons] prepend_concat_map ys f xs =
+      match ys with
+      | [] -> concat_map f xs
+      | y :: ys -> y :: prepend_concat_map ys f xs
+    in
+    function
+    | [] -> `Blocks []
+    | _ :: _ as examples ->
+      let block_of_example index (intro, ex) =
+        let prose = `I (string_of_int (index + 1) ^ ".", String.trim intro ^ ":")
+        and code_lines =
+          ex
+          |> String.trim
+          |> split_lines
+          |> concat_map (fun codeline ->
+            [ `Noblank; `Pre ("      " ^ codeline) ])
+          (* suppress initial blank *)
+          |> List.tl
         in
-        loop ~acc:(line :: acc) (j + 1) (j + 1) ~last_is_cr:false
-      | _ -> loop ~acc i (j + 1) ~last_is_cr:false
+        `Blocks (prose :: code_lines)
+      in
+      let example_blocks = examples |> List.mapi block_of_example in
+      `Blocks (`S "EXAMPLES" :: example_blocks)
   in
-  loop ~acc:[] 0 0 ~last_is_cr:false
-
-let[@tail_mod_cons] rec concat_map f = function
-  | [] -> []
-  | x :: xs -> prepend_concat_map (f x) f xs
-
-and[@tail_mod_cons] prepend_concat_map ys f xs =
-  match ys with
-  | [] -> concat_map f xs
-  | y :: ys -> y :: prepend_concat_map ys f xs
-
-let examples = function
-  | [] -> `Blocks []
-  | _ :: _ as examples ->
-    let block_of_example index (intro, ex) =
-      let prose = `I (string_of_int (index + 1) ^ ".", String.trim intro ^ ":")
-      and code_lines =
-        ex
-        |> String.trim
-        |> split_lines
-        |> concat_map (fun codeline -> [ `Noblank; `Pre ("      " ^ codeline) ])
-        (* suppress initial blank *)
-        |> List.tl
+  let refmt_t =
+    let top_level_info =
+      let doc = "Reason's Parser & Pretty-printer" in
+      let man =
+        [ `S "DESCRIPTION"
+        ; `P
+            "refmt lets you format Reason files, parse them, and convert them \
+             between OCaml syntax and Reason syntax."
+        ; examples
+            [ "Initialise a new project named `foo'", "dune init project foo"
+            ; "Format a Reason implementation file", "refmt file.re"
+            ; "Format a Reason interface file", "refmt file.rei"
+            ; ( "Format interface code from the command line"
+              , "echo 'let x: int' | refmt --interface=true" )
+            ; "Convert an OCaml file to Reason", "refmt file.ml"
+            ; "Convert a Reason file to OCaml", "refmt file.re --print ml"
+            ; ( "Convert OCaml from the command line to Reason"
+              , "echo 'let x = 1' | refmt --parse ml" )
+            ]
+        ]
       in
-      `Blocks (prose :: code_lines)
+      let version =
+        "Reason " ^ Package.version ^ " @ " ^ Package.git_short_version
+      in
+      Cmd.info "refmt" ~version ~doc ~man
     in
-    let example_blocks = examples |> List.mapi block_of_example in
-    `Blocks (`S "EXAMPLES" :: example_blocks)
-
-let top_level_info =
-  let doc = "Reason's Parser & Pretty-printer" in
-  let man =
-    [ `S "DESCRIPTION"
-    ; `P
-        "refmt lets you format Reason files, parse them, and convert them \
-         between OCaml syntax and Reason syntax."
-    ; examples
-        [ "Initialise a new project named `foo'", "dune init project foo"
-        ; "Format a Reason implementation file", "refmt file.re"
-        ; "Format a Reason interface file", "refmt file.rei"
-        ; ( "Format interface code from the command line"
-          , "echo 'let x: int' | refmt --interface=true" )
-        ; "Convert an OCaml file to Reason", "refmt file.ml"
-        ; "Convert a Reason file to OCaml", "refmt file.re --print ml"
-        ; ( "Convert OCaml from the command line to Reason"
-          , "echo 'let x = 1' | refmt --parse ml" )
-        ]
-    ]
-  in
-  let version =
-    "Reason " ^ Package.version ^ " @ " ^ Package.git_short_version
-  in
-  Cmd.info "refmt" ~version ~doc ~man
-
-let refmt_t =
-  let open Term in
-  let open Refmt_args in
-  let term =
-    const refmt
-    $ interface
-    $ recoverable
-    $ explicit_arity
-    $ parse_ast
-    $ print
-    $ print_width
-    $ heuristics_file
-    $ in_place
-    $ input
+    let open Term in
+    let open Refmt_args in
+    let term =
+      const refmt
+      $ interface
+      $ recoverable
+      $ explicit_arity
+      $ parse_ast
+      $ print
+      $ print_width
+      $ heuristics_file
+      $ in_place
+      $ input
+    in
+    Cmd.v top_level_info (Term.ret term)
   in
-  Cmd.v top_level_info (Term.ret term)
 
-let () =
   match Cmd.eval_value' refmt_t with
   | `Exit 0 -> exit 0
   | `Exit _ -> exit 1