I'm trying to make a Prolog predicate iscontained/2: iscontained(List, Search) where it returns true. if the Search is listed within the given List, false. if not. And if it is a variable that is inputted, then it just returns that it equals each element in the list.
Example:
?- iscontained([a, b, c], a).
true.
?- iscontained([a, b, c], d).
false.
?- iscontained([a, b, c], A).
A = a;
A = b;
A = c;
false.
I need a shove in the right direction, not asking for a hand out, unless you know a quick way to do it. Any help is appreciated, thanks.
You will need to consider two cases. I'll leave the body of the rules up to you.
iscontained([A|Xs],A)iscontained([X|Xs],A)[edited to remove reference to the empty list: the empty list contains nothing: if encountered, the predicate fails.]