ocamlPackages.xtmpl: fix for jsoo ≥ 3.4.0

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

@@ -15,6 +15,8 @@ stdenv.mkDerivation rec {
     sha256 = "1hq6y4rhz958q40145k4av8hx8jyvspg78xf741samd7vc3jd221";
   };
 
+  patches = [ ./jsoo.patch ];
+
   buildInputs = [ ocaml findlib ppx_tools js_of_ocaml js_of_ocaml-ppx ];
   propagatedBuildInputs = [ iri re ];
 

pkgs/development/ocaml-modules/xtmpl/jsoo.patch

@@ -0,0 +1,26 @@
+diff --git a/xtmpl_js.ml b/xtmpl_js.ml
+index e0d3894..991d1b3 100644
+--- a/xtmpl_js.ml
++++ b/xtmpl_js.ml
+@@ -25,6 +25,8 @@
+ 
+ (** *)
+ 
++open Js_of_ocaml
++
+ let log s = Firebug.console##log (Js.string s);;
+ 
+ module X = Xtmpl_rewrite
+diff --git a/xtmpl_js.mli b/xtmpl_js.mli
+index d709896..5ed471c 100644
+--- a/xtmpl_js.mli
++++ b/xtmpl_js.mli
+@@ -25,6 +25,8 @@
+ 
+ (** Convenient functions to use in JS code *)
+ 
++open Js_of_ocaml
++
+ (** Create a new tree of DOM nodes from a given XML tree.
+   Errors are logged to the firebug console.
+   @param doc Default is [Dom_html.document].