iterator.remove();
      assertEquals(initialSize - 1, map.size());

      // Use "entryCopy" instead of "entry" because "entry" might be invalidated after
      // iterator.remove().
      assertFalse(entrySet.contains(entryCopy));
      assertInvariants(map);
      assertThrows(IllegalStateException.class, iterator::remove);
    } else {
      iterator.next();

      return oldValue.getValue();
    }
  }

  @CanIgnoreReturnValue
  @Override
  public @Nullable V remove(@Nullable Object key) {
    synchronized (lock) {
      Timestamped<V> stamped = cachingHashMap.remove(key);
      if (stamped != null) {
        V value = stamped.getValue();
        // `key` was in the cache, so it's a K.

	createCallback.Remove("c1")
	if ok, msg := assertCallbacks(createCallback, []string{"c3", "c4", "c2"}); !ok {
		t.Errorf("callbacks tests failed, got %v", msg)
	}

	createCallback.Remove("c4")
	if ok, msg := assertCallbacks(createCallback, []string{"c3", "c2"}); !ok {
		t.Errorf("callbacks tests failed, got %v", msg)
	}

	createCallback.Remove("c2")

    /* Should complain on attempt to remove() after peek(). */
    assertThrows(IllegalStateException.class, () -> peekingIterator.remove());

    assertEquals(
        "After remove() throws exception, peek should still be ok", "B", peekingIterator.peek());

    /* Should recover to be able to remove() after next(). */
    assertEquals("B", peekingIterator.next());
    peekingIterator.remove();

    Set<Feature<?>> derivedFeatures = copyToSet(multimapFeatures);
    if (!derivedFeatures.remove(CollectionFeature.SERIALIZABLE_INCLUDING_VIEWS)) {
      derivedFeatures.remove(CollectionFeature.SERIALIZABLE);
    }
    if (derivedFeatures.remove(MapFeature.SUPPORTS_REMOVE)) {
      derivedFeatures.add(CollectionFeature.SUPPORTS_REMOVE);
    }
    return derivedFeatures;
  }

     * this is not possible.
     *
     * <p>This method, in contrast to {@link #remove(Object, int)}, has no effect when the element
     * count is smaller than {@code occurrences}.
     *
     * @param element the element to remove
     * @param occurrences the number of occurrences of {@code element} to remove
     * @return {@code true} if the removal was possible (including if {@code occurrences} is zero)
     */

  }

  /**
   * A sensible definition of {@link #remove(Object)} in terms of {@link #remove(Object, int)}. If
   * you override {@link #remove(Object, int)}, you may wish to override {@link #remove(Object)} to
   * forward to this implementation.
   *
   * @since 7.0
   */
  @Override
  protected boolean standardRemove(@Nullable Object element) {
    return remove(element, 1) > 0;
  }

  /**

}

func (p *processor) Register(name string, fn func(*DB)) error {
	return (&callback{processor: p}).Register(name, fn)
}

func (p *processor) Remove(name string) error {
	return (&callback{processor: p}).Remove(name)
}

func (p *processor) Replace(name string, fn func(*DB)) error {
	return (&callback{processor: p}).Replace(name, fn)
}

func (p *processor) compile() (err error) {

        return new BiMapEntry(entry);
      }

      @Override
      public void remove() {
        if (entry == null) {
          throw new IllegalStateException("no calls to next() since the last call to remove()");
        }
        V value = entry.getValue();
        iterator.remove();
        removeFromInverseMap(value);
        entry = null;
      }
    };
  }

  @WeakOuter

  public void testRemove_empty() {
    assertThrows(NoSuchElementException.class, () -> getQueue().remove());
    expectUnchanged();
  }

  @CollectionFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(ONE)
  public void testRemove_size1() {
    assertEquals("size1Queue.remove() should return first element", e0(), getQueue().remove());
    expectMissing(e0());
  }

  @CollectionFeature.Require({KNOWN_ORDER, SUPPORTS_REMOVE})