[Paul Cerkez]

I have a simple program that I believe I have solved all the syntax issue except one.

I searched the Help[ and this board for error c504

As near as I can tell, I have it correct but the complier keeps throwing the c504.

error c504 : The expression has type '() -> ::string procedure', which is incompatible with the type '::string'

Code: Select all

% The declaration:
 
class predicates
    patient : (string).  % I even made this nondeterm and I still get the C504 message.
 
clauses
    patient(S) :-
        patresponses(S),
        stdio::write("you are repeating yourself."),
        stdio::nl,
        stdio::write(": "),
        S2 = stdio::readLine,
        patient(S2).
    patient(S) :-
        assert(patresponses(S)),
        assert(temp(S)).

I am stumped, I know I am missing something simple.

Thanks,
P.

[Paul Cerkez]

I know I am missing something simple but I can't figure it out.

Could someone look this project over and tell me where I am AFU. (that c504 for one is kicking my butt, and when I do get past it, the application runs non-stop and allows no interaction.)

I know I am doing something wrong but I can't see what it is.

Right now I can't see the forest for the trees.

Thanks
P.

[Harrison Pratt]

Try this instead:

Code: Select all

        S2 = stdio::readLine()  % <== missing parentheses,

Easy mistake to make ... I've done it hundreds of times with my tired old eyes.

[Harrison Pratt]

Paul, is it your intent to recreate "The Shrink" in old style prolog syntax or migrate it to VIP 9x syntax?

[Paul Cerkez]

Harrison,
Right now I just want to get it working.

That said, I do want it working as a Console app. New way or old is irrelevant to me right now. Eventually, I will go to the new syntax.

I am also looking at a PIE exercise for the students so I don't want to introduce too much at one time as this is an "intro to AI" class.

They have already completed a CLIPS exercise that I am grading now (they had to extend the CLIPS fact/rule base). Looks like some did a good job. CLIPS is Forward Chaining. I want them to do a Backward Chaining (Prolog) problem (extend the fact/rule base) so they can learn the difference in the way the two tools solve problems.

[Harrison Pratt]

I'll take a look at it tomorrow.

[Paul Cerkez]

thanks.

[Harrison Pratt]

Paul, take a look at my notes on the zipped main.pro file. I see you don't have everything fleshed out yet -- I understand why. This is not a complete solution, but it will get you started. I tried to keep old Turbo Prolog syntax. VIP 9x code style would be much cleaner looking.