* restrictive. However, the ideal signature, {@code public <S super T> S or(S)}, is not legal
   * Java. As a result, some sensible operations involving subtypes are compile errors:
   *
   * <pre>{@code
   * Optional<Integer> optionalInt = getSomeOptionalInt();
   * Number value = optionalInt.or(0.5); // error
   *
   * FluentIterable<? extends Number> numbers = getSomeNumbers();

  @J2ktIncompatible
  @GwtIncompatible // reflection
  public void testTransformExceptionRemainsMemoized() throws Throwable {
    // We need to test with two input futures since ExecutionList.execute
    // doesn't catch Errors and we cannot depend on the order that our
    // transformations run. (So it is possible that the Error being thrown
    // could prevent our second transformations from running).

   * Function<A, B> or who call convertAll (and for any checkers that apply @PolyNull-like semantics
   * to Converter.convert). So maybe we don't want to think too hard about how to prevent our
   * checkers from issuing errors related to LegacyConverter, since it turns out that
   * LegacyConverter does violate the assumptions we make elsewhere.
   */

  @CheckForNull
  private B unsafeDoForward(@CheckForNull A a) {

  }

  /**
   * Returns an {@code InputStream} that decodes base-encoded input from the specified {@code
   * Reader}. The returned stream throws a {@link DecodingException} upon decoding-specific errors.
   */
  @J2ktIncompatible
  @GwtIncompatible // Reader,InputStream
  public abstract InputStream decodingStream(Reader reader);

  /**

    } catch (Exception e) { // sneaky checked exception
      // Log it and keep going -- bad runnable and/or executor. Don't punish the other runnables if
      // we're given a bad one. We only catch Exception because we want Errors to propagate up.
      log.get()
          .log(
              Level.SEVERE,
              "RuntimeException while executing runnable "
                  + runnable
                  + " with executor "

   *
   * <p>This is guaranteed to return zero if the dataset contains a single pair of finite values. It
   * is not guaranteed to return zero when the dataset consists of the same pair of values multiple
   * times, due to numerical errors.
   *
   * <h3>Non-finite values</h3>
   *
   * <p>If the dataset contains any non-finite values ({@link Double#POSITIVE_INFINITY}, {@link

import com.google.common.annotations.GwtCompatible;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/** A utility method to perform unchecked casts to suppress errors produced by nullness analyses. */
@GwtCompatible
@ElementTypesAreNonnullByDefault
final class NullnessCasts {
  /**
   * Accepts a {@code @Nullable T} and returns a plain {@code T}, without performing any check that

      }
    }

    /*
     * TODO(cpovirk): `return (V) removedValue` once our checker permits that.
     *
     * (We promoted a class of warnings into errors because sometimes they indicate real problems.
     * But now we need to "undo" some instance of spurious errors, as discussed in
     * https://github.com/jspecify/checker-framework/issues/8.)
     */
    return removedValue == null ? null : (V) removedValue;
  }

        if (firstTimeSeeingThisException) {
          log(throwable);
          return;
        }
      }
    }

    /*
     * TODO(cpovirk): Should whenAllComplete().call*() log errors, too? Currently, it doesn't call
     * handleException() at all.
     */
    if (throwable instanceof Error) {
      /*
       * TODO(cpovirk): Do we really want to log this if we called setException(throwable) and it

  @J2ktIncompatible
  @GwtIncompatible // reflection
  public void testTransformExceptionRemainsMemoized() throws Throwable {
    // We need to test with two input futures since ExecutionList.execute
    // doesn't catch Errors and we cannot depend on the order that our
    // transformations run. (So it is possible that the Error being thrown
    // could prevent our second transformations from running).