I have a base resource which is use by almost all of the resources in the project, the base resource contains extensions like AshPostgres and AshArchival which seems to work just fine.

Now i am trying to add a base filter for AshArchival.
Since i have never done anything with marcos i am a bit confused on how to approach this.

The base resource looks like this:

defmodule App.BaseResource do
  # ...	

  defmacro __using__(opts) do
    opts =
      opts
      |> Keyword.merge(
        [extensions: [AshPaperTrail.Resource, AshArchival.Resource]],
        fn _key, extensions, base_extensions ->
          Enum.uniq(extensions ++ base_extensions)
        end
      )
      |> Keyword.put(:data_layer, AshPostgres.DataLayer)

    quote do
      use Ash.Resource, unquote(opts)

      paper_trail do
        change_tracking_mode :changes_only
        belongs_to_actor :user, App.Accounts.User, domain: App.Accounts
        store_action_name? true
      end

      attributes do
        create_timestamp :inserted_at
        update_timestamp :updated_at
      end

      # 
      # resource do
      #   base_filter expr(is_nil(archived_at)) # <-- archived_at is an undefined variable
      # end
      # actions do
      #   read :archived do
      #     filter expr(not is_nil(archived_at)) # <-- 
      #   end

      postgres do
        table App.BaseResource.tablename(__MODULE__)
        repo App.Repo
        base_filter_sql "archived_at IS NULL"
      end
    end
  end
end