Consider the following Prolog program:
test(X,Y) :-
( X 0 - Y = positive ; Y = nonpositive ).
What value(s), if any, will be returned for Y by the following query?
?- test(3,Y).

Question

Consider the following Prolog program: 
 test(X,Y) :- 
      ( X > 0 -> Y = positive ; Y = nonpositive ). 
 What value(s), if any, will be returned for  Y   by the following query? 
 ?- test(3,Y).

Answer

Y = positive , the only solution.

Answer

None of the above. In Prolog, a statement of the form  (Condition -> Then; Else)  can only be used in queries, not in bodies of rules as in the example above.

Answer

First, Prolog returns  Y = positive . Then, on backtracking, it also returns  Y = nonpositive , because  (Condition->Then;Else)  does not commit to the  Then  branch and Prolog will explore the  Else  branch as an alternative solution.

Answer

Y = nonpositive , the only solution.

Crowdly

Consider the following Prolog program: test(X,Y) :- ( X > 0 -> Y = posi...

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