add the 'zed' ocaml editor library

pkgs/development/ocaml-modules/zed/default.nix

@@ -0,0 +1,34 @@
+{stdenv, fetchurl, ocaml, findlib, camomile, ocaml_react}:
+
+stdenv.mkDerivation rec {
+  version = "1.3";
+  name = "ocaml-zed-${version}";
+
+  src = fetchurl {
+    url = https://github.com/diml/zed/archive/1.3.tar.gz;
+    sha256 = "1fr9xzf5msdnl2wx279aqj051nqbhs6v9aq1mfpv3r1mrqvrrfwj";
+  };
+
+  buildInputs = [ ocaml findlib ocaml_react];
+
+  propagatedBuildInputs = [ camomile ];
+
+  createFindlibDestdir = true;
+
+  meta = {
+    description = "Abstract engine for text edition in OCaml";
+    longDescription = ''
+    Zed is an abstract engine for text edition. It can be used to write text editors, edition widgets, readlines, ...
+
+    Zed uses Camomile to fully support the Unicode specification, and implements an UTF-8 encoded string type with validation, and a rope datastructure to achieve efficient operations on large Unicode buffers. Zed also features a regular expression search on ropes.
+
+    To support efficient text edition capabilities, Zed provides macro recording and cursor management facilities.
+    '';
+    homepage = https://github.com/diml/zed;
+    license = stdenv.lib.licenses.bsd3;
+    platforms = ocaml.meta.platforms;
+    maintainers = [
+      stdenv.lib.maintainers.gal_bolle
+    ];
+  };
+}

pkgs/top-level/all-packages.nix

@@ -3370,6 +3370,9 @@ let
     yojson = callPackage ../development/ocaml-modules/yojson { };
 
     zarith = callPackage ../development/ocaml-modules/zarith { };
+
+    zed = callPackage ../development/ocaml-modules/zed { };
+
   };
 
   ocamlPackages = recurseIntoAttrs ocamlPackages_4_01_0;