syntax errors help 1

[200878456]

getting this error:

| ?- Computer(X) :- Mac(X).
! Syntax error
! operator expected after expression
! in line 20
! Computer
! <<here>>
! ( X ) :- Mac ( X ) .
| ?-

any ideas what's wrong?

 

[joel76]

In SWI-Prolog, you can't write "Computer(X) :- Mac(X)." at top level.
It must be written in a file of rules.
Also, don't forget that a fonctor begins with a lowercase caracter e.g. "computer(X) :- mac(X)."
Uppercase letters begin variables.

 

[200878456]

So I have to write this in notepad, and then import it?

thanks

 

[joel76]

Yes, if you use Linux, with Microsoft, you have an integrated editor.

 

[200878456]

thanks, just one more question

I have:

memory(laptop, 512mb).

and it gives me syntax error.... looks like it doesn't like the numbers, is there any way to have "512mb" or do I have to write it as a word?

 

[200878456]

what's wrong here?

os(jacobsdesktop, windows).

I'm getting an error:

* clauses for users/2 are not together

I also tried:

os(X, windows) :- jacobsdesktop(X).

but getting the same error :S

any ideas?

 

[joel76]

* clauses for users/2 are not together"
In your file, you must write your clauses one following the others.
you must not have

 rule1 :-
..........
..........

rule2 :-
...........
...........

rule1 :-
.............
.............

 

[200878456]

so how should I write it? The problem is because I have "os" for a laptop and for a desktop

so

os(jacobsdesktop, windows).

and

os(jacobslaptop, mac).

how would I write it?

 

[joel76]

I don't understand where is your problem.
You write the two facts in the database

os(jacobsdesktop, windows).
os(jacobslaptop, mac).

 

[200878456]

thanks