*/
  public static CharSource concat(CharSource... sources) {
    return concat(ImmutableList.copyOf(sources));
  }

  /**
   * Returns a view of the given character sequence as a {@link CharSource}. The behavior of the
   * returned {@code CharSource} and any {@code Reader} instances created by it is unspecified if
   * the {@code charSequence} is mutated while it is being read, so don't do that.
   *

import com.google.common.annotations.VisibleForTesting;

/**
 * Implementation of Geoff Pike's fingerprint2011 hash function. See {@link Hashing#fingerprint2011}
 * for information on the behaviour of the algorithm.
 *
 * <p>On Intel Core2 2.66, on 1000 bytes, fingerprint2011 takes 0.9 microseconds compared to
 * fingerprint at 4.0 microseconds and md5 at 4.5 microseconds.
 *

          throw new AssertionFailedError("You weren't supposed to actually invoke me!");
        }
      };

  public void testAnyAndNone_logicalOps() throws Exception {
    // These are testing behavior that's never promised by the API, but since
    // we're lucky enough that these do pass, it saves us from having to write
    // more excruciating tests! Hooray!

    assertSame(CharMatcher.any(), CharMatcher.none().negate());

       * ClassNotFoundException thereafter.
       *
       * Android API level 26 and JVM8 both let our Error propagate directly the first time and
       * throw NoClassDefFoundError thereafter. This is the proper behavior according to the spec.
       * See https://docs.oracle.com/javase/specs/jls/se8/html/jls-12.html#jls-12.4.2 (steps #11 and
       * #5).
       *
       * Note that that "first time" might happen in a test other than

            CollectionFeature.RESTRICTS_ELEMENTS,
            CollectionSize.ANY)
        .suppressing(suppressForEnumSet())
        .createTestSuite();
  }

  /**
   * Tests regular NavigableSet behavior of synchronizedNavigableSet(treeSet); does not test the
   * fact that it's synchronized.
   */
  public Test testsForSynchronizedNavigableSet() {
    return NavigableSetTestSuiteBuilder.using(

 * rangeSet.add(Range.openClosed(0, 0)); // empty range; {[1, 10], [11, 20)}
 * rangeSet.remove(Range.open(5, 10)); // splits [1, 10]; {[1, 5], [10, 10], [11, 20)}
 * }</pre>
 *
 * <p>Note that the behavior of {@link Range#isEmpty()} and {@link Range#isConnected(Range)} may not
 * be as expected on discrete ranges. See the Javadoc of those methods for details.
 *

        if ((makeBehavior != null && !makeBehavior.isEmpty()) && !makeUpstream && !makeDownstream) {
            throw new MavenExecutionException("Invalid reactor make behavior: " + makeBehavior, request.getPom());
        }

        if (makeUpstream || makeDownstream) {
            Set<MavenProject> projectsSet = new HashSet<>(projects);

such as those in the <a href="/pkg/sync/"><code>sync</code></a>
and <a href="/pkg/sync/atomic/"><code>sync/atomic</code></a> packages.
</p>

<p>
If you must read the rest of this document to understand the behavior of your program,
you are being too clever.
</p>

<p>
Don't be clever.
</p>

<h3 id="overview">Informal Overview</h3>

<p>

    var_name: string for name of environment variable, e.g. "TF_NEED_CUDA".
    query_item: string for feature related to the variable, e.g. "CUDA for
      Nvidia GPUs".
    enabled_by_default: boolean for default behavior.
    question: optional string for how to ask for user input.
    yes_reply: optional string for reply when feature is enabled.
    no_reply: optional string for reply when feature is disabled.

  Returns:

   * according to spec.
   *
   * <p>This ordering is not serializable, as its implementation relies on {@link
   * System#identityHashCode(Object)}, so its behavior cannot be preserved across serialization.
   *
   * @since 2.0
   */
  // TODO(kevinb): copy to Comparators, etc.
  @J2ktIncompatible // MapMaker
  public static Ordering<@Nullable Object> arbitrary() {