unikernel/duniverse/ppxlib/ast/pp/dune

@@ -0,0 +1,6 @@
+(executables
+ (names pp)
+ (libraries supported_version)
+ (flags :standard -w -3))
+
+(ocamllex pp_rewrite)

unikernel/duniverse/ppxlib/ast/pp/pp.ml

@@ -0,0 +1,16 @@
+let () =
+  match Sys.argv with
+  | [| _; ocaml_version_str; fname |] ->
+      let ocaml_version =
+        match Supported_version.of_string ocaml_version_str with
+        | Some v -> string_of_int (Supported_version.to_int v)
+        | None ->
+            Printf.eprintf "Unknown OCaml version %s\n" ocaml_version_str;
+            exit 1
+      in
+      let ic = open_in_bin fname in
+      Printf.printf "# 1 %S\n" fname;
+      Pp_rewrite.rewrite ocaml_version (Lexing.from_channel ic)
+  | _ ->
+      Printf.eprintf "%s: <ocaml-version> <file-name>\n" Sys.executable_name;
+      exit 2

unikernel/duniverse/ppxlib/ast/pp/pp.mli

@@ -0,0 +1 @@
+(* empty *)

unikernel/duniverse/ppxlib/ast/pp/pp_rewrite.mli

@@ -0,0 +1 @@
+val rewrite : string -> Lexing.lexbuf -> unit

unikernel/duniverse/ppxlib/ast/pp/pp_rewrite.mll

@@ -0,0 +1,27 @@
+{
+open Printf
+
+let print_ocaml_version version =
+  let patt_len = String.length "OCAML_VERSION" in
+  (* Note: the spaces in the replacements are to preserve locations *)
+  printf "%-*s" patt_len version
+}
+
+rule rewrite ocaml_version = parse
+  | "OCAML_VERSION"
+    { print_ocaml_version ocaml_version;
+      rewrite ocaml_version lexbuf
+    }
+  |          "(*IF_AT_LEAST " ([^'*' ' ']* as v) " " ([^'*']* as s) "*)"
+    { let chunk = if (v <= ocaml_version)
+        then "              " ^ String.make (String.length v + 1) ' ' ^ s ^          "  "
+        else Lexing.lexeme lexbuf
+      in
+      print_string chunk;
+      rewrite ocaml_version lexbuf
+    }
+  | _ as c
+    { print_char c;
+      rewrite ocaml_version lexbuf
+    }
+  | eof { () }