@GwtCompatible
final class Absent<T> extends Optional<T> {
  static final Absent<Object> INSTANCE = new Absent<>();

  @SuppressWarnings("unchecked") // implementation is "fully variant"
  static <T> Optional<T> withType() {
    return (Optional<T>) INSTANCE;
  }

  private Absent() {}

  @Override
  public boolean isPresent() {
    return false;
  }

  @Override

   * is a power of two. Indexing uses masked per-thread hash codes.
   * Nearly all declarations in this class are package-private,
   * accessed directly by subclasses.
   *
   * Table entries are of class Cell; a variant of AtomicLong padded
   * to reduce cache contention on most processors. Padding is
   * overkill for most Atomics because they are usually irregularly
   * scattered in memory and thus don't interfere much with each

      --add-opens java.base/sun.security.jca=ALL-UNNAMED
    </test.add.opens>
    <module.status>integration</module.status>
    <variant.jvmEnvironment>android</variant.jvmEnvironment>
    <variant.jvmEnvironmentVariantName>android</variant.jvmEnvironmentVariantName>
    <otherVariant.version>999.0.0-HEAD-jre-SNAPSHOT</otherVariant.version>
    <otherVariant.jvmEnvironment>standard-jvm</otherVariant.jvmEnvironment>

   * is a power of two. Indexing uses masked per-thread hash codes.
   * Nearly all declarations in this class are package-private,
   * accessed directly by subclasses.
   *
   * Table entries are of class Cell; a variant of AtomicLong padded
   * to reduce cache contention on most processors. Padding is
   * overkill for most Atomics because they are usually irregularly
   * scattered in memory and thus don't interfere much with each

```

oder

```
http://127.0.0.1:8000/items/foo?short=on
```

oder

```
http://127.0.0.1:8000/items/foo?short=yes
```

gehen, oder zu irgendeiner anderen Variante der Groß-/Kleinschreibung (Alles groß, Anfangsbuchstabe groß, usw.), dann wird Ihre Funktion den Parameter `short` mit dem `bool`-Wert `True` sehen, ansonsten mit dem Wert `False`.

Ainsi, même avec le code ci‑dessus qui n'emploie pas explicitement Pydantic, FastAPI utilise Pydantic pour convertir ces dataclasses standard en la variante de dataclasses de Pydantic.

Et bien sûr, cela prend en charge la même chose :

* validation des données
* sérialisation des données
* documentation des données, etc.

func isSysErrTooManySymlinks(err error) bool {
	return errors.Is(err, syscall.ELOOP)
}

// Check if the given error corresponds to ENOTEMPTY for unix,
// EEXIST for solaris variants,
// and ERROR_DIR_NOT_EMPTY for windows (directory not empty).
func isSysErrNotEmpty(err error) bool {
	if errors.Is(err, syscall.ENOTEMPTY) {
		return true
	}

import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import org.jspecify.annotations.Nullable;

/**
 * Unchecked variant of {@link java.util.concurrent.ExecutionException}. As with {@code
 * ExecutionException}, the exception's {@linkplain #getCause() cause} comes from a failed task,
 * possibly run in another thread.
 *

La CLI `fastapi` tentera de détecter automatiquement l’application FastAPI à exécuter, en supposant qu’il s’agit d’un objet nommé `app` dans un fichier `main.py` (ou quelques autres variantes).

Mais vous pouvez configurer explicitement l’application à utiliser.

## Configurer le `entrypoint` de l’application dans `pyproject.toml` { #configure-the-app-entrypoint-in-pyproject-toml }

Beispielsweise verwendet der Google Login OpenID Connect (welches seinerseits OAuth2 verwendet).

Aber der Facebook Login unterstützt OpenID Connect nicht. Es hat seine eigene Variante von OAuth2.

### OpenID (nicht „OpenID Connect“) { #openid-not-openid-connect }

Es gab auch eine „OpenID“-Spezifikation. Sie versuchte das Gleiche zu lösen wie **OpenID Connect**, basierte aber nicht auf OAuth2.