*
     * <p>This method is used when testing iterators without a known ordering. We poll the target
     * iterator's next element and pass it to the reference iterator through this method so it can
     * return the same element. This enables the assertion to pass and the reference iterator to
     * properly update its state.
     */
    void promoteToNext(E e) {
      if (nextElements.remove(e)) {
        nextElements.push(e);

		{[]string{"https://localhost:9000/d1", "https://localhost:9001/d2", "https://localhost:9002/d3", "https://localhost:9003/d4"}, nil},
		// // It is valid WRT endpoint list that same path is expected with different port on same server.
		{[]string{"https://127.0.0.1:9000/d1", "https://127.0.0.1:9001/d1", "https://127.0.0.1:9002/d1", "https://127.0.0.1:9003/d1"}, nil},

The next sections assume you already read the main [Tutorial - User Guide: Security](../../tutorial/security/index.md){.internal-link target=_blank}.

        endpoint: Callable[..., Any],
        *,
        name: Optional[str] = None,
        dependencies: Optional[Sequence[params.Depends]] = None,
        dependency_overrides_provider: Optional[Any] = None,
    ) -> None:
        self.path = path
        self.endpoint = endpoint
        self.name = get_name(endpoint) if name is None else name
        self.dependencies = list(dependencies or [])

var GlobalContext, cancelGlobalContext = context.WithCancel(context.Background())

// restartProcess starts a new process passing it the active fd's. It
// doesn't fork, but starts a new process using the same environment and
// arguments as when it was originally started. This allows for a newly
// deployed binary to be started. It returns the pid of the newly started
// process when successful.
func restartProcess() error {

            parameter = {
                "name": name,
                "in": param_type.value,
                "required": param.required,
                "schema": param_schema,
            }
            if field_info.description:
                parameter["description"] = field_info.description
            openapi_examples = getattr(field_info, "openapi_examples", None)

						return nil, setupType,
							config.ErrInvalidErasureEndpoints(nil).Msg(fmt.Sprintf("same path '%s' can not be served by different port on same address", endpoint.Path))
					}
					pathIPMap[endpoint.Path] = IPSet.Union(hostIPSet)
				} else {
					pathIPMap[endpoint.Path] = hostIPSet
				}
			}
		}

		// Check whether same path is used for more than 1 local endpoints.
		{

      // reentrant calls will see that their current thread is the same as the one set in
      // latestTaskQueue, and queue rather than calling execute() directly.
      ThreadConfinedTaskQueue executingTaskQueue = new ThreadConfinedTaskQueue();
      executingTaskQueue.thread = currentThread;
      /*
       * requireNonNull is safe because we don't null out `sequencer` except:
       *

   * exactly one entry for each distinct element in the multiset (thus it always has the same size
   * as the {@link #elementSet}). The order of the elements in the element set is unspecified.
   *
   * <p>The entry set is backed by the same data as the multiset, so any change to either is
   * immediately reflected in the other. However, multiset changes may or may not be reflected in

These examples are intentionally simple, but show how it all works.

In the chapters about security, there are utility functions that are implemented in this same way.

If you understood all this, you already know how those utility tools for security work underneath.

///