Conditionally Assign Empty Array

I want to conditionally assign to an array either

• an array value or
• to empty the array.

So in the code below, what do I replace XXXXXX with to empty the array?

<dmx-array id="this_array" dmx-bind:items="contact.data.contact.contact_regions!=&quot&quot ? contact.data.contact.contact_regions.split(&quot,&quot) : XXXXXXX"></dmx-array>

Best wishes,
Antony.