use dune-site

example/css_path.ml

@@ -0,0 +1,14 @@
+(* get leaflet.css path from dune-site *)
+
+let dune_site = List.filter Sys.file_exists Mysites.Sites.css
+
+let lookup_file filename =
+  List.find_map
+    (fun dir ->
+      let filename' = Filename.concat dir filename in
+      if Sys.file_exists filename' then Some filename' else None )
+    dune_site
+
+let leaflet_css = lookup_file "leaflet.css" |> Option.get
+
+let () = Format.printf "%s@." leaflet_css