The snippet I posted can easily be made into a generic function<T> that takes a collection<T> and a predicate<T>. For example, the Apache Commons library offers

The snippet I posted can easily be made into a generic function<T> that takes a collection<T> and a predicate<T>. For example, the Apache Commons library offers such a function for Java, so where available the code comes down to the fairly similar CollectionUtils.filter(collection, predicate); Of course aside from being a bit more verbose, predicate needs to be an object (often a singleton), because you can't pass around functions.