assertThat(tags[String::class]).isEqualTo("hello")
    assertThat(tags[Integer::class]).isEqualTo(5)
  }

  /** The implementation retains no nodes from the original linked list. */
  @Test
  fun replaceFirstElement() {
    val tags =
      EmptyTags
        .plus(String::class, "a")
        .plus(Integer::class, 5 as Integer)
        .plus(Boolean::class, true)
        .plus(String::class, "b")