// +optional
  optional string reason = 2;

  // EvaluationError is an indication that some error occurred during the authorization check.
  // It is entirely possible to get an error and be able to continue determine authorization status in spite of it.
  // For instance, RBAC can be missing a role, but enough roles are still present and bound to reason about the request.
  // +optional

import java.util.regex.Pattern;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Generates fresh instances of types that are different from each other (if possible).
 *
 * @author Ben Yu
 */
@GwtIncompatible
@J2ktIncompatible
class FreshValueGenerator {

  private static final ImmutableMap<Class<?>, Method> GENERATORS;

  static {

   * processing and may run concurrently, for example, if the JVM flag {@code
   * -XX:+ExplicitGCInvokesConcurrent} is used.
   *
   * <p>Whenever possible, it is preferable to test directly for some observable change resulting
   * from GC, as with {@link #awaitClear}. Because there are no guarantees for the order of GC

* components

## **FastAPI** plug-ins

Integrations and "plug-ins" can be built using the **Dependency Injection** system. But in fact, there is actually **no need to create "plug-ins"**, as by using dependencies it's possible to declare an infinite number of integrations and interactions that become available to your *path operation functions*.

{!../../docs_src/path_params/tutorial003b.py!}
```

The first one will always be used since the path matches first.

## Predefined values

If you have a *path operation* that receives a *path parameter*, but you want the possible valid *path parameter* values to be predefined, you can use a standard Python <abbr title="Enumeration">`Enum`</abbr>.

### Create an `Enum` class

# Démarrage

Le fichier **FastAPI** le plus simple possible pourrait ressembler à cela  :

```Python
{!../../docs_src/first_steps/tutorial001.py!}
```

Copiez ce code dans un fichier nommé `main.py`.

Démarrez le serveur :

<div class="termy">

```console
$ uvicorn main:app --reload

<span style="color: green;">INFO</span>:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)

   * @throws IllegalArgumentException if bracketless IPv6 is detected.
   */
  @CanIgnoreReturnValue
  public HostAndPort requireBracketsForIPv6() {
    checkArgument(!hasBracketlessColons, "Possible bracketless IPv6 literal: %s", host);
    return this;
  }

  @Override
  public boolean equals(@CheckForNull Object other) {
    if (this == other) {
      return true;
    }

   * suitable for testing that map entries cannot be modified via a nefarious implementation of
   * equals. This is used for testing unmodifiable collections of map entries; for example, it
   * should not be possible to access the raw (modifiable) map entry via a nefarious equals method.
   */
  public static <K extends @Nullable Object, V extends @Nullable Object>
      Entry<K, V> nefariousMapEntry(K key, V value) {

  }

  // Element Mutation

  @Test
  public void addEdge_existingNodes() {
    assume().that(graphIsMutable()).isTrue();

    // Adding nodes initially for safety (insulating from possible future
    // modifications to proxy methods)
    addNode(N1);
    addNode(N2);
    assertThat(networkAsMutableNetwork.addEdge(N1, N2, E12)).isTrue();
    assertThat(network.edges()).contains(E12);

  }

  // Element Mutation

  @Test
  public void addEdge_existingNodes() {
    assume().that(graphIsMutable()).isTrue();

    // Adding nodes initially for safety (insulating from possible future
    // modifications to proxy methods)
    addNode(N1);
    addNode(N2);
    assertThat(networkAsMutableNetwork.addEdge(N1, N2, E12)).isTrue();
    assertThat(network.edges()).contains(E12);