}
    }.test();
  }

  @GwtIncompatible // fairly slow (~40s)
  public void testConcatSingletonAndSingletonYieldsDoubleton() {
    new DoubletonIteratorTester() {
      @Override
      protected Iterator<Integer> newTargetIterator() {
        return Iterators.concat(iterateOver(1), iterateOver(2));
      }
    }.test();
  }

  @GwtIncompatible // fairly slow (~40s)

r:#dc3545;--light:#f8f9fa;--dark:#343a40;--breakpoint-xs:0;--breakpoint-sm:576px;--breakpoint-md:768px;--breakpoint-lg:992px;--breakpoint-xl:1200px;--font-family-sans-serif:"Source Sans Pro",-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji","Segoe UI Symbol";--font-family-monospace:SFMono-Regular,Menlo,Monaco,Consolas,"Liberation Mono","Courier New",monospace}*,::after,::before{box-sizing:border-box}html{font-family:sans-ser...

In GitHub, the template will guide you to write the right question so that you can more easily get a good answer, or even solve the problem yourself even before asking. And in GitHub I can make sure I always answer everything, even if it takes some time. I can't personally do that with the chat systems. 😅

# Templates { #templates }

You can use any template engine you want with **FastAPI**.

A common choice is Jinja2, the same one used by Flask and other tools.

There are utilities to configure it easily that you can use directly in your **FastAPI** application (provided by Starlette).

## Install dependencies { #install-dependencies }

## Conditional OpenAPI from settings and env vars { #conditional-openapi-from-settings-and-env-vars }

You can easily use the same Pydantic settings to configure your generated OpenAPI and the docs UIs.

For example:

{* ../../docs_src/conditional_openapi/tutorial001.py hl[6,11] *}

participant execute as Ejecutar función

    rect rgba(0, 255, 0, .1)
        code ->> function: say_hi(name="Camila")
        function ->> execute: ejecutar código de la función
        execute ->> code: devolver el resultado
    end

    rect rgba(0, 255, 255, .1)
        code ->> function: say_hi(name="Camila")
        function ->> code: devolver resultado almacenado
    end

    rect rgba(0, 255, 0, .1)

   * its runtime check.
   *
   * <p>An example use case for this method is in implementing an {@code Iterator<T>} whose {@code
   * next} field is lazily initialized. The type of that field would be {@code @Nullable T}, and the
   * code would be responsible for populating a "real" {@code T} (which might still be the value

# À propos de HTTPS

Il est facile de penser que HTTPS peut simplement être "activé" ou non.

Mais c'est beaucoup plus complexe que cela.

/// tip

Si vous êtes pressé ou si cela ne vous intéresse pas, passez aux sections suivantes pour obtenir des instructions étape par étape afin de tout configurer avec différentes techniques.

///

Pour apprendre les bases du HTTPS, du point de vue d'un utilisateur, consultez <a href="https://howhttps.works/"

* **Intuitif** : Excellente compatibilité avec les IDE. <abbr title="également connu sous le nom d'auto-complétion, autocomplétion, IntelliSense">Complétion</abbr> complète. Moins de temps passé à déboguer.
* **Facile** : Conçu pour être facile à utiliser et à apprendre. Moins de temps passé à lire la documentation.
* **Concis** : Diminue la duplication de code. De nombreuses fonctionnalités liées à la déclaration de chaque paramètre. Moins de bugs.

import java.util.Map;
import java.util.TreeMap;
import java.util.WeakHashMap;
import java.util.concurrent.ConcurrentHashMap;

/**
 * Utility class for easily creating and setting values in {@link Map} instances.
 * <p>
 * By statically importing this class, you can easily initialize {@literal Map} instances as follows:
 * </p>
 *
 * <pre>
 * import static org.codelibs.core.collection.Maps.*;
 *