Backport re to OCaml 4.08

dune-project

@@ -21,7 +21,7 @@
  (name re)
  (synopsis "RE is a regular expression library for OCaml")
  (depends
-  (ocaml (>= 4.12.0))
+  (ocaml (>= 4.08.0))
   (ppx_expect :with-test)
   (ounit2 :with-test)
   (js_of_ocaml :with-test))

lib/emacs.ml

@@ -21,6 +21,7 @@
 *)
 
 module Re = Core
+open Import
 
 exception Parse_error
 exception Not_supported

lib/fake/atomic.ml

@@ -0,0 +1,10 @@
+type 'a t = 'a ref
+
+let make x = ref x
+let get x = !x
+let set atomic v = atomic := v
+
+let fetch_and_add atomic n =
+  let v = !atomic in
+  atomic := v + n;
+  v

lib/import.ml

@@ -1,4 +1,19 @@
-module List = Stdlib.ListLabels
+module List = struct
+  let[@warning "-32"] rec equal ~eq l1 l2 = match l1, l2 with
+    | [], [] -> true
+    | [], _::_ | _::_, [] -> false
+    | x::xs, y::ys -> if eq x y then equal ~eq xs ys else false
+
+  let[@warning "-32"] rec compare ~cmp l1 l2 = match l1, l2 with
+    | [], [] -> 0
+    | [], _::_ -> -1
+    | _::_, [] -> 1
+    | x::xs, y::ys ->
+        let r = cmp x y in
+        if r = 0 then compare ~cmp xs ys else r
+
+  include Stdlib.ListLabels
+end
 
 module Poly = struct
   let equal = ( = )
@@ -13,12 +28,13 @@ let ( = ) = Int.equal
 let ( == ) = [ `Use_phys_equal ]
 let ( < ) (x : int) (y : int) = x < y
 let ( > ) (x : int) (y : int) = x > y
-let min = Int.min
-let max = Int.max
+let min (x : int) (y : int) = if x <= y then x else y
+let max (x : int) (y : int) = if x >= y then x else y
 let compare = Int.compare
 
 module Int = struct
   let[@warning "-32"] hash (x : int) = Hashtbl.hash x
+  let[@warning "-32"] max (x : int) (y : int) = if x >= y then x else y
 
   include Stdlib.Int
 end

re.opam

@@ -23,7 +23,7 @@ homepage: "https://github.com/ocaml/ocaml-re"
 bug-reports: "https://github.com/ocaml/ocaml-re/issues"
 depends: [
   "dune" {>= "3.15"}
-  "ocaml" {>= "4.12.0"}
+  "ocaml" {>= "4.08.0"}
   "ppx_expect" {with-test}
   "ounit2" {with-test}
   "js_of_ocaml" {with-test}