static <A, B> L<B> lambdaMapLike lambdaMap(IF1<A, B> f, Iterable<A> l) {
  ret map(l, f);
}

// with currying
static <A, B, C> L<C> lambdaMapLike lambdaMap(IF2<A, B, C> f, B b, Iterable<A> l) {
  ret map(l, c -> f.get(b, c));
}