# 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

Stellen Sie sicher, dass Sie `yield` nur einmal pro Abhängigkeit verwenden.

     * <p>
     * If a root package is specified at instance construction, the specified class name is interpreted as a relative name from the root package.
     * </p>
     *
     * @param className the class name
     * @return <code>true</code> if the class file exists in the resources handled by this instance
     */

}

@Override
public boolean exists() throws IOException {
    if (isDirectory() && directoryLeaseManager != null) {
        // Check parent directory cache first
        String parentPath = getParent();
        DirectoryCacheEntry parentCache = directoryLeaseManager.getCacheEntry(parentPath);
        
        if (parentCache != null && parentCache.isComplete()) {
            boolean exists = parentCache.hasChild(getName());

                        installationSettingsPath != null && Files.exists(installationSettingsPath)
                                ? Sources.fromPath(installationSettingsPath)
                                : null)
                .projectSettingsSource(
                        projectSettingsPath != null && Files.exists(projectSettingsPath)
                                ? Sources.fromPath(projectSettingsPath)

            if (Os.IS_WINDOWS) {
                Path tool = bin.resolve(toolName + ".exe");
                if (Files.exists(tool)) {
                    return tool;
                }
            }
            Path tool = bin.resolve(toolName);
            if (Files.exists(tool)) {
                return tool;
            }
        }
        return null;
    }

# Dependencies with yield { #dependencies-with-yield }

FastAPI supports dependencies that do some <abbr title='sometimes also called "exit code", "cleanup code", "teardown code", "closing code", "context manager exit code", etc.'>extra steps after finishing</abbr>.

To do this, use `yield` instead of `return`, and write the extra steps (code) after.

/// tip

Make sure to use `yield` one single time per dependency.

///

/// note | Technical Details

		echo "A root disk is formatted unexpectedely"
		cat "${WORK_DIR}/server4.log"
		exit -1
	fi
}

function cleanup() {
	pkill minio
	sudo umount ${WORK_DIR}/mnt/disk{1..3}/
	sudo rm /dev/minio-loopdisk*
	rm -rf "$WORK_DIR"
}

(prepare_block_devices)
(main "$@")
rv=$?

cleanup

     * @return true if the rule was successfully removed, false otherwise
     */
    boolean removeRule(Rule rule);

    /**
     * Checks if the specified rule exists.
     *
     * @param rule the rule to check for existence
     * @return true if the rule exists, false otherwise
     */
    boolean hasRule(Rule rule);

		writeErrorResponse(ctx, w, errorCodes.ToAPIErr(s3Error), r.URL)
		return
	}

	// Before proceeding validate if bucket exists.
	_, err := objAPI.GetBucketInfo(ctx, bucket, BucketOptions{})
	if err != nil {
		writeErrorResponse(ctx, w, toAPIError(ctx, err), r.URL)
		return
	}

	aclHeader := r.Header.Get(xhttp.AmzACL)
	if aclHeader == "" {

    }

    /**
     * Exception for intentional exit: No message or anything will be displayed, just the
     * carried exit code will be returned from invoker {@link Invoker#invoke(InvokerRequest)} method.
     */
    public static final class ExitException extends InvokerException {
        private final int exitCode;

        public ExitException(int exitCode) {
            super("EXIT");
            this.exitCode = exitCode;
        }