module Hamster::CoreExt::Enumerable

def self.included(base)
  base.class_eval do
    def to_list
      list = EmptyList
      reverse_each { |item| list = list.cons(item) }
      list
    end
  end
end

def to_list
  list = EmptyList
  reverse_each { |item| list = list.cons(item) }
  list
end