From 19ab478d9c672c3d36035bb86f9407615f4bd28a Mon Sep 17 00:00:00 2001
From: craff <christophe@raffalli.eu>
Date: Sun, 19 Dec 2021 22:30:18 -1000
Subject: [PATCH] filter_map is only available in recent Stdlib

---
 src/Tiny_httpd.ml       |  2 +-
 src/Tiny_httpd_util.ml  | 12 ++++++++++++
 src/Tiny_httpd_util.mli |  4 ++++
 3 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/src/Tiny_httpd.ml b/src/Tiny_httpd.ml
index 7fa86283..89c99233 100644
--- a/src/Tiny_httpd.ml
+++ b/src/Tiny_httpd.ml
@@ -396,7 +396,7 @@ module Headers = struct
                 | _       -> None
               in
               let cookies =
-                List.filter_map fn_eq (String.split_on_char ';' v) @ cookies
+                U.filter_map fn_eq (String.split_on_char ';' v) @ cookies
               in
               (headers, cookies)
             end
diff --git a/src/Tiny_httpd_util.ml b/src/Tiny_httpd_util.ml
index 703bc329..a5a001d9 100644
--- a/src/Tiny_httpd_util.ml
+++ b/src/Tiny_httpd_util.ml
@@ -102,6 +102,18 @@ let split_on_slash s : _ list =
   done;
   List.rev !l
 
+let filter_map f l =
+  let rec fn = function
+    | [] -> []
+    | x::l ->
+       begin
+         match f x with
+         | None -> fn l
+         | Some x -> x::fn l
+       end
+  in
+  fn l
+
 (*$= & ~printer:Q.Print.(list string)
   ["a"; "b"] (split_on_slash "/a/b")
   ["coucou"; "lol"] (split_on_slash "/coucou/lol")
diff --git a/src/Tiny_httpd_util.mli b/src/Tiny_httpd_util.mli
index d53ae32e..fffacfd5 100644
--- a/src/Tiny_httpd_util.mli
+++ b/src/Tiny_httpd_util.mli
@@ -40,3 +40,7 @@ val pp_date : Format.formatter -> Unix.tm -> unit
     for expiration date of cookies.
     @since 0.12
 *)
+
+val filter_map : ('a -> 'b option) -> 'a list -> 'b list
+(** filter_map, now in Stdlib
+    @since 0.12 *)