# 使用yield的依赖项

FastAPI支持在完成后执行一些<abbr title='有时也被称为"退出"("exit")，"清理"("cleanup")，"拆卸"("teardown")，"关闭"("close")，"上下文管理器"("context managers")。 ...'>额外步骤</abbr>的依赖项.

为此，你需要使用 `yield` 而不是 `return`，然后再编写这些额外的步骤（代码）。

/// tip | 提示

确保在每个依赖中只使用一次 `yield`。

///

/// note | "技术细节"

任何一个可以与以下内容一起使用的函数：

	defer testlogger.T.SetErrorTB(t)()
	errFatal := func(err error) {
		t.Helper()
		if err != nil {
			t.Fatal(err)
		}
	}
	grid, err := SetupTestGrid(2)
	errFatal(err)
	t.Cleanup(grid.Cleanup)

	local := grid.Managers[0]
	localHost := grid.Hosts[0]
	remote := grid.Managers[1]
	remoteHost := grid.Hosts[1]

	connLocalToRemote := local.Connection(remoteHost)

 * entries may be counted in {@link Cache#size}, but will never be visible to read or write
 * operations.
 *
 * <p>Certain cache configurations will result in the accrual of periodic maintenance tasks which
 * will be performed during write operations, or during occasional read operations in the absence of

# Abhängigkeiten mit yield

FastAPI unterstützt Abhängigkeiten, die nach Abschluss einige <abbr title="Manchmal auch genannt „Exit Code“, „Cleanup Code“, „Teardown Code“, „Closing Code“, „Kontext Manager Exit Code“, usw.">zusätzliche Schritte ausführen</abbr>.

Verwenden Sie dazu `yield` statt `return` und schreiben Sie die zusätzlichen Schritte / den zusätzlichen Code danach.

/// tip | "Tipp"

    public static final String CRAWLING_USER_AGENT_PROPERTY = "crawling.user.agent";

    public static final String DAY_FOR_CLEANUP_PROPERTY = "day.for.cleanup";

    public static final String WEB_API_JSON_PROPERTY = "web.api.json";

    public static final String WEB_API_SUGGEST_PROPERTY = "web.api.suggest";

  - [Changes by Kind](#changes-by-kind-3)
    - [API Change](#api-change)
    - [Feature](#feature-3)
    - [Bug or Regression](#bug-or-regression-3)
    - [Other (Cleanup or Flake)](#other-cleanup-or-flake)
  - [Dependencies](#dependencies-3)
    - [Added](#added-3)
    - [Changed](#changed-3)
    - [Removed](#removed-3)
- [v1.24.13](#v12413)
  - [Downloads for v1.24.13](#downloads-for-v12413)

	// We stagger listings only on HDDs.
	if info.Rotational == nil || *info.Rotational {
		s.rotational = true
		s.walkMu = &sync.Mutex{}
		s.walkReadMu = &sync.Mutex{}
	}

	if cleanUp {
		bgFormatErasureCleanupTmp(s.drivePath) // cleanup any old data.
	}

	formatData, formatFi, err := formatErasureMigrate(s.drivePath)
	if err != nil && !errors.Is(err, os.ErrNotExist) {
		if os.IsPermission(err) {

	// Object operations.

	// GetObjectNInfo returns a GetObjectReader that satisfies the
	// ReadCloser interface. The Close method runs any cleanup
	// functions, so it must always be called after reading till EOF
	//
	// IMPORTANTLY, when implementations return err != nil, this
	// function MUST NOT return a non-nil ReadCloser.

#include "tensorflow/c/eager/c_api_experimental.h"
#include "tensorflow/c/eager/c_api_test_util.h"
#include "tensorflow/c/eager/custom_device_testutil.h"
#include "tensorflow/c/tf_status.h"
#include "tensorflow/core/lib/gtl/cleanup.h"
#include "tensorflow/core/platform/test.h"

TEST(CUSTOM_DEVICE, RegisterSimpleDevice) {
  std::unique_ptr<TF_Status, decltype(&TF_DeleteStatus)> status(
      TF_NewStatus(), TF_DeleteStatus);

# Dependências com yield

O FastAPI possui suporte para dependências que realizam <abbr title='também chamados de "código de saída", "código de cleanup", "código de teardown", "código de finalização", "código de saída para gerenciador de contextos", etc.'>alguns passos extras ao finalizar</abbr>.

Para fazer isso, utilize `yield` em vez de `return`, e escreva os passos extras (código) depois.

/// tip | "Dica"

Garanta que `yield` é utilizado apenas uma vez.