Allows the predicate defined by X to be used as an arithmetic function.
Examples
squared(X,Y) :- Y is X * X.
?- squared(3,X).
X = 9
yes
?- X is squared(3).
Cannot find arithmetic operator: squared/1
?- arithmetic_function(squared/1).
yes
?- X is squared(3).
X = 9
yes always_fails(X, Y) :- fail.
?- arithmetic_function(always_fails/1).
yes
?- X is always_fails(3).
Could not evaluate: always_fails/2 for: always_fails(3)