Available on jvm
comparator():Comparator<Dynamic>
entrySet():Set<Map_Entry<K, V>>
firstKey():K
headMap(param1:K):SortedMap<K, V>
keySet():Set<K>
lastKey():K
subMap(param1:K, param2:K):SortedMap<K, V>
tailMap(param1:K):SortedMap<K, V>
values():Collection<V>