Use of unsafe partial in this situation

How do I use unsafePartial for something like this:

{ list1: [x, y, z] } = d

where I know for a fact that this covers all cases?

I don’t understand that code snippet. What is d?

A record of type { list1 :: Array Int }

I think this is one option.

unsafePartial $ case d.list1 of [x, y, z] -> ...