ctx.get(), {x.get()}, absl::MakeSpan(outputs),
                            /*use_function=*/!std::get<2>(GetParam()));
  ASSERT_EQ(error::INVALID_ARGUMENT, s.code());
  ASSERT_EQ(
      "Provided null gradient_function for 'Neg'.\nIf the intent is to treat "
      "this op as non-differentiable consider using RegisterNotDifferentiable "
      "or NotDifferentiableGradientFunction.",
      s.message());

 * behavior of {@link #addAll}, which can lead to unexpected behavior. In this case, you should
 * override {@code addAll} as well, either providing your own implementation, or delegating to the
 * provided {@code standardAddAll} method.
 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code
 * default} methods. Instead, it inherits their default implementations. When those implementations

 * lead to unexpected behavior. In this case, you should override {@code add(Object)} as well,
 * either providing your own implementation, or delegating to the provided {@code standardAdd}
 * method.
 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code

 *
 * <ul>
 *   <li>Multiple events for the same listener are never dispatched concurrently.
 *   <li>Events for the different listeners are dispatched concurrently.
 *   <li>All events for a given listener dispatch on the provided {@link #executor}.
 *   <li>It is easy for the user to ensure that listeners are never invoked while holding locks.
 * </ul>
 *
 * The last point is subtle. Often the observable object will be managing its own internal state

	s.cniListenServerCancel()
}

// Start starts up a UDS server which receives events from the CNI chain plugin.
func (s *CniPluginServer) Start() error {
	if s.sockAddress == "" {
		return fmt.Errorf("no socket address provided")
	}
	log.Infof("starting listener for CNI plugin events at %v", s.sockAddress)
	unixListener, err := pluginlistener.NewListener(s.sockAddress)
	if err != nil {
		return fmt.Errorf("failed to create CNI listener: %v", err)

   * {@link LoadingCache#get(Object) get(K)} method instead of this one.
   *
   * <p>Among the improvements that this method and {@code LoadingCache.get(K)} both provide are:
   *
   * <ul>
   *   <li>{@linkplain LoadingCache#get(Object) awaiting the result of a pending load} rather than
   *       starting a redundant one
   *   <li>eliminating the error-prone caching boilerplate

import java.nio.charset.Charset;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * An abstract implementation of {@link Hasher}, which only requires subtypes to implement {@link
 * #putByte}. Subtypes may provide more efficient implementations, however.
 *
 * @author Dimitris Andreou
 */
@ElementTypesAreNonnullByDefault
abstract class AbstractHasher implements Hasher {
  @Override
  @CanIgnoreReturnValue

```Python hl_lines="1  46-47"
{!../../docs_src/websockets/tutorial001.py!}
```

/// note | "Technical Details"

You could also use `from starlette.websockets import WebSocket`.

**FastAPI** provides the same `WebSocket` directly just as a convenience for you, the developer. But it comes directly from Starlette.

///

## Await for messages and send messages

import org.junit.jupiter.api.Test
import org.junit.jupiter.api.Timeout
import org.junit.jupiter.api.extension.RegisterExtension
import org.junit.jupiter.params.ParameterizedTest
import org.junit.jupiter.params.provider.ValueSource

@Flaky // STDOUT logging enabled for test
@Timeout(30)
@Tag("Slow")
open class ConnectionListenerTest {
  @RegisterExtension
  val platform = PlatformRule()

  @RegisterExtension

import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import java.util.logging.Level;

/**
 * A manager for monitoring and controlling a set of {@linkplain Service services}. This class
 * provides methods for {@linkplain #startAsync() starting}, {@linkplain #stopAsync() stopping} and
 * {@linkplain #servicesByState inspecting} a collection of {@linkplain Service services}.