Node* node = graph->graph.FindNodeId(*pos);
    // FindNodeId() returns nullptr for nodes that have been deleted.
    // We aren't currently allowing nodes to be deleted, but it is safer
    // to still check.
    if (node != nullptr) return ToOperation(node);
    *pos += 1;
  }

  // No more nodes.
  return nullptr;
}

// * size_t is used to represent byte sizes of objects that are
//   materialized in the address space of the calling process.
// * int is used as an index into arrays.
// * Deletion functions are safe to call on nullptr.
//
// Questions left to address:
// * Might at some point need a way for callers to provide their own Env.
// * Maybe add TF_TensorShape that encapsulates dimension info.
//
// Design decisions made:

         * only possible value for the type parameter is <E>, since otherwise the
         * MultiExceptionListIterator wouldn't be an Iterator<E>. The cast is safe, even though
         * javac can't tell.
         */
        @SuppressWarnings("unchecked")
        MultiExceptionListIterator multiExceptionListIterator =
            (MultiExceptionListIterator) reference;

      @SuppressWarnings("unchecked")
      K key = (K) stream.readObject();
      @SuppressWarnings("unchecked")
      V value = (V) stream.readObject();
      /*
       * requireNonNull is safe for a properly serialized multimap: We've already inserted a
       * collection for each key that we expect.
       */
      requireNonNull(map.get(key)).add(value);
    }
    setMap(map);
  }

     */
    Throwable failureCause() {
      checkState(
          state == FAILED,
          "failureCause() is only valid if the service has failed, service is %s",
          state);
      // requireNonNull is safe because the constructor requires a non-null cause with state=FAILED.
      return requireNonNull(failure);
    }
  }

<code>l.TryLock</code> (or <code>l.TryRLock</code>)
may be considered to be able to return false
even when the mutex <i>l</i> is unlocked.
</p>

<h3 id="once">Once</h3>

<p>
The <code>sync</code> package provides a safe mechanism for
initialization in the presence of multiple goroutines
through the use of the <code>Once</code> type.
Multiple threads can execute <code>once.Do(f)</code> for a particular <code>f</code>,

     */
    fun ping(
      ack: Boolean,
      payload1: Int,
      payload2: Int,
    )

    /**
     * The peer tells us to stop creating streams. It is safe to replay streams with
     * `ID > lastGoodStreamId` on a new connection.  In- flight streams with
     * `ID <= lastGoodStreamId` can only be replayed on a new connection if they are idempotent.
     *

     * AOSP grief.
     */
    return new AbstractList<StackTraceElement>() {
      /*
       * The following requireNonNull calls are safe because we use jlaStackTrace() only if
       * lazyStackTraceIsLazy() returns true.
       */
      @Override
      public StackTraceElement get(int n) {
        return (StackTraceElement)

import java.util.stream.LongStream;

/**
 * A mutable object which accumulates double values and tracks some basic statistics over all the
 * values added so far. The values may be added singly or in groups. This class is not thread safe.
 *
 * @author Pete Gillin
 * @author Kevin Bourrillion
 * @since 20.0
 */
@J2ktIncompatible
@GwtIncompatible
public final class StatsAccumulator {
  /** Creates a new accumulator. */

         * only possible value for the type parameter is <E>, since otherwise the
         * MultiExceptionListIterator wouldn't be an Iterator<E>. The cast is safe, even though
         * javac can't tell.
         */
        @SuppressWarnings("unchecked")
        MultiExceptionListIterator multiExceptionListIterator =
            (MultiExceptionListIterator) reference;