ocamlPackages.lablgtk: 2.18.5 -> 2.18.6

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

@@ -1,18 +1,24 @@
 { stdenv, fetchurl, ocaml, findlib, pkgconfig, gtk2, libgnomecanvas, libglade, gtksourceview }:
 
-let
-  pname = "lablgtk";
+let param =
+  let check = stdenv.lib.versionAtLeast ocaml.version; in
+  if check "4.06" then {
+    version = "2.18.6";
+    url = https://forge.ocamlcore.org/frs/download.php/1726/lablgtk-2.18.6.tar.gz;
+    sha256 = "1y38fdvswy6hmppm65qvgdk4pb3ghhnvz7n4ialf46340r1s5p2d";
+  } else if check "3.12" then {
+    version = "2.18.5";
+    url = https://forge.ocamlcore.org/frs/download.php/1627/lablgtk-2.18.5.tar.gz;
+    sha256 = "0cyj6sfdvzx8hw7553lhgwc0krlgvlza0ph3dk9gsxy047dm3wib";
+  } else throw "lablgtk is not available for OCaml ${ocaml.version}";
 in
 
-assert stdenv.lib.versionAtLeast ocaml.version "3.12";
-
 stdenv.mkDerivation rec {
-  name = "${pname}-${version}";
-  version = "2.18.5";
+  name = "lablgtk-${version}";
+  inherit (param) version;
 
   src = fetchurl {
-    url = https://forge.ocamlcore.org/frs/download.php/1627/lablgtk-2.18.5.tar.gz;
-    sha256 = "0cyj6sfdvzx8hw7553lhgwc0krlgvlza0ph3dk9gsxy047dm3wib";
+    inherit (param) url sha256;
   };
 
   nativeBuildInputs = [ pkgconfig ];