Rules with Builtin : listLength can not trigger

Hello there

I got the link that have many builtin function and I want to use the
listLength( ?l , ?len) in my own rules.

Here is my rules :

[TestList: ( ?x yago:created ?l)
listLength(?l, ?len)

(?x yago:HasCreated ?len)

I count it manually , there should be more than ten facts can be triggered
by this rules.

Can someone give some example to deal with listLength(?l , ?len)