func LastIndexFunc(s []byte, f func(r rune) bool) int {
	return lastIndexFunc(s, f, true)
}

// indexFunc is the same as IndexFunc except that if
// truth==false, the sense of the predicate function is
// inverted.
func indexFunc(s []byte, f func(r rune) bool, truth bool) int {
	start := 0
	for start < len(s) {
		r, wid := utf8.DecodeRune(s[start:])
		if f(r) == truth {
			return start
		}
		start += wid
	}

Let's take this application as example:

{* ../../docs_src/query_params_str_validations/tutorial001_py310.py hl[7] *}

The query parameter `q` is of type `str | None`, that means that it's of type `str` but could also be `None`, and indeed, the default value is `None`, so FastAPI will know it's not required.

/// note

FastAPI will know that the value of `q` is not required because of the default value `= None`.

     * merged, but overlapping ranges will cause an exception when {@link #build()} is called.
     *
     * @throws IllegalArgumentException if any inserted ranges are empty
     * @since 21.0
     */
    @CanIgnoreReturnValue
    public Builder<C> addAll(Iterable<Range<C>> ranges) {
      for (Range<C> range : ranges) {
        add(range);
      }

    frame.writeByte(FLAG_END_HEADERS or FLAG_PRIORITY)
    frame.writeInt(expectedStreamId and 0x7fffffff)
    frame.writeInt(0) // Independent stream.
    frame.writeByte(255) // Heaviest weight, zero-indexed.
    frame.writeAll(headerBytes)
    reader.nextFrame(
      requireSettings = false,
      object : BaseTestHandler() {
        override fun priority(
          streamId: Int,
          streamDependency: Int,

    }
  }

  // TODO(cpovirk): Rename to "toCharSequence."
  CharSequence toString(@Nullable Object part) {
    /*
     * requireNonNull is not safe: Joiner.on(...).join(somethingThatContainsNull) will indeed throw.
     * However, Joiner.on(...).useForNull(...).join(somethingThatContainsNull) *is* safe -- because
     * it returns a subclass of Joiner that overrides this method to tolerate null inputs.
     *

 * encoding} may be viewed as a {@code CharSource} using {@link ByteSource#asCharSource(Charset)}.
 *
 * <p><b>Note:</b> In general, {@code CharSource} is intended to be used for "file-like" sources
 * that provide readers that are:
 *
 * <ul>
 *   <li><b>Finite:</b> Many operations, such as {@link #length()} and {@link #read()}, will either

      nextSibling.previous = node;
      nextSibling.previousSibling = node;
    }
    size++;
    return node;
  }

  /**
   * Removes the specified node from the linked list. This method is only intended to be used from
   * the {@code Iterator} classes. See also {@link LinkedListMultimap#removeAllNodes(Object)}.
   */
  private void removeNode(Node<K, V> node) {
    if (node.previous != null) {

 * encoding} may be viewed as a {@code CharSource} using {@link ByteSource#asCharSource(Charset)}.
 *
 * <p><b>Note:</b> In general, {@code CharSource} is intended to be used for "file-like" sources
 * that provide readers that are:
 *
 * <ul>
 *   <li><b>Finite:</b> Many operations, such as {@link #length()} and {@link #read()}, will either

        int nameIndex = xmlOutput.indexOf("<name>");
        int descriptionIndex = xmlOutput.indexOf("<description>");
        int urlIndex = xmlOutput.indexOf("<url>");

        // Verify description is inserted between name and url
        assertTrue(nameIndex < descriptionIndex, "name should come before description");
        assertTrue(descriptionIndex < urlIndex, "description should come before url");
    }

    @Test

     * returns 0, but if we had a SingletonImmutableSortedSet, this might no
     * longer be the case.)
     *
     * javax.naming.Name and java.util.concurrent.Delayed might work, but
     * they're fairly obscure, we've invented our own interface and class.
     */
    Interface a = new Impl();
    Interface b = new Impl();
    ImmutableSortedSet<Interface> set = ImmutableSortedSet.of(a, b);
    Object[] unused1 = set.toArray();