高效Drools评估数组或集合中的元素

Using Drools 3.0.6 (old, I know), what is an efficient evaluation for finding a fact in a known, fixed and quite large array or collection (the inverse of contains, i.e. "is contained in"). Using an OR series of normal "equals" results in StackOverflowError as the array/collection can contain a few thousand entries, as the Drools binary operator evaluation is recursive.Using Drools 3.0.6 (old, I know), what is an ef