partition method

Tuple2<IList<A>, IList<A>> partition(
  1. bool f(
    1. A a
    )
)

Implementation

Tuple2<IList<A>, IList<A>> partition(bool f(A a)) =>
  foldRight(tuple2(nil(), nil()), (A a, acc) => f(a)
    ? acc.map1((xs) => cons(a, xs))
    : acc.map2((xs) => cons(a, xs)));