[rasvprolog]

I would appreciate if anyone can suggest proper punctuation for an OR operator. DeBoer Guide suggests";" but using that causes error. In the example below the following predicate succeeds if xpositive2(_,1,9) AND xpositive2(_,4,11) both are true. If the intention is for the predicate to succeed if xpositive2(_,1,9) OR xpositive2(_,4,11) either one is true, what is the proper punctuation.

Code: Select all

cause("Success",CFI,CFO):-
                xpositive2(_,1,9),
                xpositive2(_,4,11),             
                CFO=CFI+0.05,!.

Thanks in advance,
Frank

[Harrison Pratt]

Parentheses are your friends!

Code: Select all

    cause("Success", CFI, CFO) :-
        (xpositive2(_, 1, 9) or xpositive2(_, 4, 11)),
        CFO = CFI + 0.05,
        !.

Also, if you use ";" as a substitute for "or" the IDE will politely change ";" to "or" to use the more visually obvious form!

[rasvprolog]

Harrison, Thank you Thank you....