I have created a fairly unexciting custom type (Event) and an equally vanilla custom taxonomy (Venue). Whenever a user creates an Event, I want them to be required to either create a new Venue or select an existing Venue. How can I make this a required field when publishing?
It seems like the sort of thing that should be rather trivial but I've been going up and down http://codex.wordpress.org/Function_Reference/register_taxonomy and haven't found anything obvious. Am I going about this in the wrong way?
Any assistance would be appreciated.