ref: a27a5c52f5efeac5165b4dddcb90f207853cc1f5
dir: /example.pl/
:- dynamic(math/4). math(A,B,C,D) :- D is A + B + C * A. parentest :- 1 + 2 * 3 + 4. parentest :- (0 * (1 + 2) * 3) * 3 + 4. true. likes(bob, ice). likes(sam, text). likes(sam, ice). could_be_friends(Person1, Person2) :- likes(Person1, Thing1), likes(Person2, Thing2), !, Thing1 = Thing2. list1(A) :- A = [1,2,3,4]. list2(A) :- A = [a,b|c]. curly(A) :- A = {one,two,three}.