-- record data:
caption title:
optional string link:
-- data list bar:
-- bar: Data
-- bar: Hello
link: yes
-- foo: $obj.title
$loop$: $bar as $obj
link: $obj.link
-- ftd.row foo:
caption title:
optional string link:
--- ftd.text: $title
--- ftd.text: Not Null
if: $link is not null
--- ftd.text: Null
if: $link is null