I guess you can finally cross that one off of your bucket list. I know it has been there for a very long time. 
However, what if the predicate has more than one choice point, wouldn’t the answer be a list?
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A post was split to a new topic: Print last choice point - Reply 2
It prints only the last choice point left (if any) in the current environment:
From SWI-Prolog -- Manual
Unify Choice with an integer provided a reference to the last choice point. Fails if the current environment has no choice points. See also prolog_choice_attribute/3.