5.1 Janus class Query

Class janus.Query() is similar to the janus.once() function, but it returns a Python iterator that allows for iterating over the answers to a non-deterministic Prolog predicate.

Query janus.Query(query, bindings={}, keep=False)

As janus.once(), returning an iterator that provides an answer dict as janus.once() for each answer to query. Answers never have truth False. See discussion above.

dict|None janus.Query.next()

Explicitly ask for the next solution of the iterator. Normally, using the Query as an iterator is to be preferred. See discussion above.

None janus.Query.close()

Close the query. Closing a query is obligatory. When used as an iterator, the Python destructor (__del__()) takes care of closing the query.