description: |
        Please describe the problem as concisely as possible.
    validations:
      required: true
  - type: textarea
    id: context
    attributes:
      label: Context (optional)
      description: |
        How has this issue affected you? What are you trying to accomplish?
        Providing context helps us come up with a solution that is most useful in the real world
    validations:

    }

    @Test
    @DisplayName("createContext accepts null/empty optional parameters")
    void createContext_edge_parameters_ok() throws Exception {
        TestCredentials creds = new TestCredentials("D", false, false, new Subject(), false);
        // Intentionally pass null/empty values for optional parameters; expect no exception
        SSPContext ctx1 = creds.createContext(mockContext, null, "", null, false);

import org.codelibs.fess.dict.stemmeroverride.StemmerOverrideItem;
import org.codelibs.fess.util.ComponentUtil;
import org.codelibs.fess.util.RenderDataUtil;
import org.dbflute.optional.OptionalEntity;
import org.dbflute.optional.OptionalThing;
import org.lastaflute.web.Execute;
import org.lastaflute.web.response.ActionResponse;
import org.lastaflute.web.response.HtmlResponse;
import org.lastaflute.web.response.render.RenderData;

Ebenfalls können Sie es verwenden, um automatisch Code für Clients zu generieren, die mit Ihrer API kommunizieren. Zum Beispiel für Frontend-, Mobile- oder IoT-Anwendungen.

### Ihre App deployen (optional) { #deploy-your-app-optional }

Sie können optional Ihre FastAPI-App in der <a href="https://fastapicloud.com" class="external-link" target="_blank">FastAPI Cloud</a> deployen, treten Sie der Warteliste bei, falls Sie es noch nicht getan haben. 🚀

    if (allowsNullKeys) {
      boolean unused = map.containsKey(null);
    } else {
      try {
        boolean unused2 = map.containsKey(null);
      } catch (NullPointerException optional) {
      }
    }
    assertInvariants(map);
  }

  public void testContainsValue() {
    Map<K, V> map;
    V unmappedValue;
    try {
      map = makePopulatedMap();

import com.google.common.annotations.GwtCompatible;
import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.util.Set;

/**
 * Optional features of classes derived from {@code Set}.
 *
 * @author George van den Driessche
 */
@SuppressWarnings("rawtypes") // maybe avoidable if we rework the whole package?
@GwtCompatible

                            "name": "query",
                            "in": "query",
                        }
                    ],
                }
            },
            "/query/optional": {
                "get": {
                    "responses": {
                        "200": {
                            "description": "Successful Response",

///

/// note

**FastAPI** saura que `q` est optionnel grâce au `=None`.

Le `Optional` dans `Optional[str]` n'est pas utilisé par **FastAPI** (**FastAPI** n'en utilisera que la partie `str`), mais il servira tout de même à votre éditeur de texte pour détecter des erreurs dans votre code.

///

    assertThat(ArbitraryInstances.get(Object.class)).isNotNull();
    assertEquals(0, ArbitraryInstances.get(Number.class));
    assertEquals(UTF_8, ArbitraryInstances.get(Charset.class));
    assertEquals(Optional.empty(), ArbitraryInstances.get(Optional.class));
    assertEquals(OptionalInt.empty(), ArbitraryInstances.get(OptionalInt.class));
    assertEquals(OptionalLong.empty(), ArbitraryInstances.get(OptionalLong.class));

import com.google.common.collect.testing.features.TesterAnnotation;
import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.util.Set;

/**
 * Optional features of classes derived from {@code Multimap}.
 *
 * @author Louis Wasserman
 */
@SuppressWarnings("rawtypes") // maybe avoidable if we rework the whole package?
@GwtCompatible