mkOcamlPackages: simpler rule for lablgtk

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

@@ -6,6 +6,8 @@ let
   version = "2.16.0";
 in
 
+assert stdenv.lib.versionAtLeast ocaml_version "3.12";
+
 stdenv.mkDerivation (rec {
   name = "${pname}-${version}";
   src = fetchurl {

pkgs/top-level/all-packages.nix

@@ -3375,13 +3375,9 @@ let
     lablgtk_2_14 = callPackage ../development/ocaml-modules/lablgtk/2.14.0.nix {
       inherit (gnome) libgnomecanvas libglade gtksourceview;
     };
-
-    lablgtk =
-      if lib.strings.versionAtLeast (builtins.parseDrvName ocaml.name).version "3.12"
-      then callPackage ../development/ocaml-modules/lablgtk {
-        inherit (gnome) libgnomecanvas libglade gtksourceview;
-      }
-      else lablgtk_2_14;
+    lablgtk = callPackage ../development/ocaml-modules/lablgtk {
+      inherit (gnome) libgnomecanvas libglade gtksourceview;
+    };
 
     lablgtkmathview = callPackage ../development/ocaml-modules/lablgtkmathview {
       gtkmathview = callPackage ../development/libraries/gtkmathview { };
@@ -3492,8 +3488,10 @@ let
   };
 
   ocamlPackages = recurseIntoAttrs ocamlPackages_4_01_0;
-  ocamlPackages_3_10_0 = mkOcamlPackages ocaml_3_10_0 pkgs.ocamlPackages_3_10_0;
-  ocamlPackages_3_11_2 = mkOcamlPackages ocaml_3_11_2 pkgs.ocamlPackages_3_11_2;
+  ocamlPackages_3_10_0 = (mkOcamlPackages ocaml_3_10_0 pkgs.ocamlPackages_3_10_0)
+  // { lablgtk = ocamlPackages_3_10_0.lablgtk_2_14; };
+  ocamlPackages_3_11_2 = (mkOcamlPackages ocaml_3_11_2 pkgs.ocamlPackages_3_11_2)
+  // { lablgtk = ocamlPackages_3_11_2.lablgtk_2_14; };
   ocamlPackages_3_12_1 = mkOcamlPackages ocaml_3_12_1 pkgs.ocamlPackages_3_12_1;
   ocamlPackages_4_00_1 = mkOcamlPackages ocaml_4_00_1 pkgs.ocamlPackages_4_00_1;
   ocamlPackages_4_01_0 = mkOcamlPackages ocaml_4_01_0 pkgs.ocamlPackages_4_01_0;