public static <T extends @Nullable Object> boolean removeIf(
      Iterable<T> removeFrom, Predicate<? super T> predicate) {
    if (removeFrom instanceof RandomAccess && removeFrom instanceof List) {
      return removeIfFromRandomAccessList((List<T>) removeFrom, checkNotNull(predicate));
    }
    return Iterators.removeIf(removeFrom.iterator(), predicate);
  }

   */
  @CanIgnoreReturnValue
  public static boolean retainAll(Iterable<?> removeFrom, Collection<?> elementsToRetain) {
    return (removeFrom instanceof Collection)
        ? ((Collection<?>) removeFrom).retainAll(checkNotNull(elementsToRetain))
        : Iterators.retainAll(removeFrom.iterator(), elementsToRetain);
  }

  /**

    }
    assertEquals(-1, matcher.lastIndexIn(""));
    assertFalse(matcher.matchesAnyOf(""));
    assertTrue(matcher.matchesAllOf(""));
    assertTrue(matcher.matchesNoneOf(""));
    assertEquals("", matcher.removeFrom(""));
    assertEquals("", matcher.replaceFrom("", 'z'));
    assertEquals("", matcher.replaceFrom("", "ZZ"));
    assertEquals("", matcher.trimFrom(""));
    assertEquals(0, matcher.countIn(""));
  }

    while (removeFrom.hasNext()) {
      if (elementsToRemove.contains(removeFrom.next())) {
        removeFrom.remove();
        result = true;
      }
    }
    return result;
  }

  /**
   * Removes every element that satisfies the provided predicate from the iterator. The iterator
   * will be left exhausted: its {@code hasNext()} method will return {@code false}.
   *

    }
    assertEquals(-1, matcher.lastIndexIn(""));
    assertFalse(matcher.matchesAnyOf(""));
    assertTrue(matcher.matchesAllOf(""));
    assertTrue(matcher.matchesNoneOf(""));
    assertEquals("", matcher.removeFrom(""));
    assertEquals("", matcher.replaceFrom("", 'z'));
    assertEquals("", matcher.replaceFrom("", "ZZ"));
    assertEquals("", matcher.trimFrom(""));
    assertEquals(0, matcher.countIn(""));
  }

   * Returns a string containing all non-matching characters of a character sequence, in order. For
   * example:
   *
   * {@snippet :
   * CharMatcher.is('a').removeFrom("bazaar")
   * }
   *
   * ... returns {@code "bzr"}.
   */
  public String removeFrom(CharSequence sequence) {
    String string = sequence.toString();
    int pos = indexIn(string);
    if (pos == -1) {
      return string;
    }