StackOverflowError with infinite terms

[s-webber]

Infinite terms (also known as "cyclic terms") cause a StackOverflowError.

Example:

X = p(X).

[s-webber]

Note that the unify_with_occurs_check/2 predicate can be used instead of =/2 to guard against the creation of cyclic terms during unification. #157

Examples:

?- unify_with_occurs_check(X, p(Y)).

X = p(Y)
Y = Y

yes

?- unify_with_occurs_check(X, p(X)).

no