11.3 Engine predicate reference
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Availability:built-in
Source[det]engine_next_reified(+Engine, -Term)
Similar to engine_next/2, but instead of success, failure or or raising an exception, Term is unified with one of terms below. This predicate is provided primarily for compatibility with Lean Prolog.
the(Answer)
Goal succeeded with Template bound to Answer or Goal yielded with a term Answer.
no
Goal failed.
throw(Exception)
Goal raised Exception.