Seeking clarification of datepicker UI core dependency

Seeking clarification of datepicker UI core dependency


I'm in the process of switching from one big UI file to UI core +
individual interactions / widgets based on the needs of each page.
I found when I had a page using datepicker without UI core that
datepicker seems to work just fine without the UI core.
When I go to the custom UI download, I can select datepicker without
it telling me I need the UI core file - unlike every other item.
However, when
I go to the datepicker documentation page, it lists UI core under
dependencies.
I'm assuming since it works, it works, but I'm wondering if there are
some features that might be off limits without using UI core that I'm
just not
using right now. Will it always be this way, or will I need worry
about future versions needing UI core when datepicker is used?