svoid test_StringTrie() {
  Map<S, Int> map = littreemap("hello" := 1, "hella" := 2);
  assertEquals(map, asStringTrie(map).asMap());
  map.put("hell" := 3);
  assertEquals(map, asStringTrie(map).asMap());
  
  map = litcimap("HE" := 1, "hello" := 2);
  assertEquals(map, assertCIMap(asStringTrie(map).asMap()));
}