ck endpoint call.
	 *
	 * @since 3.1.0
	 *
	 * @return bool Whether the query is for a trackback endpoint call.
	 */
	public function is_trackback() {
		return (bool) $this->is_trackback;
	}

	/**
	 * Determines whether the query is for an existing year archive.
	 *
	 * @since 3.1.0
	 *
	 * @return bool Whether the query is for an existing year archive.
	 */
	public function is_year() {
		return (bool) $this->is_year;
	}

	/**
	 * Determines whether the query is a 404 (returns no results).
	 *
	 * @since 3.1.0
	 *
	 * @return bool Whether the query is a 404 error.
	 */
	public function is_404() {
		return (bool) $this->is_404;
	}

	/**
	 * Determines whether the query is for an embedded post.
	 *
	 * @since 4.4.0
	 *
	 * @return bool Whether the query is for an embedded post.
	 */
	public function is_embed() {
		return (bool) $this->is_embed;
	}

	/**
	 * Determines whether the query is the main query.
	 *
	 * @since 3.3.0
	 *
	 * @global WP_Query $wp_query WordPress Query object.
	 *
	 * @return bool Whether the query is the main query.
	 */
	public function is_main_query() {
		global $wp_the_query;
		return $wp_the_query === $this;
	}

	/**
	 * Sets up global post data.
	 *
	 * @since 4.1.0
	 * @since 4.4.0 Added the ability to pass a post ID to `$post`.
	 *
	 * @global int     $id
	 * @global WP_User $authordata
	 * @global string  $currentday
	 * @global string  $currentmonth
	 * @global int     $page
	 * @global array   $pages
	 * @global int     $multipage
	 * @global int     $more
	 * @global int     $numpages
	 *
	 * @param WP_Post|object|int $post WP_Post instance or Post ID/object.
	 * @return true True when finished.
	 */
	public function setup_postdata( $post ) {
		global $id, $authordata, $currentday, $currentmonth, $page, $pages, $multipage, $more, $numpages;

		if ( ! ( $post instanceof WP_Post ) ) {
			$post = get_post( $post );
		}

		if ( ! $post ) {
			return;
		}

		$elements = $this->generate_postdata( $post );
		if ( false === $elements ) {
			return;
		}

		$id           = $elements['id'];
		$authordata   = $elements['authordata'];
		$currentday   = $elements['currentday'];
		$currentmonth = $elements['currentmonth'];
		$page         = $elements['page'];
		$pages        = $elements['pages'];
		$multipage    = $elements['multipage'];
		$more         = $elements['more'];
		$numpages     = $elements['numpages'];

		/**
		 * Fires once the post data has been set up.
		 *
		 * @since 2.8.0
		 * @since 4.1.0 Introduced `$query` parameter.
		 *
		 * @param WP_Post  $post  The Post object (passed by reference).
		 * @param WP_Query $query The current Query object (passed by reference).
		 */
		do_action_ref_array( 'the_post', array( &$post, &$this ) );

		return true;
	}

	/**
	 * Generates post data.
	 *
	 * @since 5.2.0
	 *
	 * @param WP_Post|object|int $post WP_Post instance or Post ID/object.
	 * @return array|false Elements of post or false on failure.
	 */
	public function generate_postdata( $post ) {

		if ( ! ( $post instanceof WP_Post ) ) {
			$post = get_post( $post );
		}

		if ( ! $post ) {
			return false;
		}

		$id = (int) $post->ID;

		$authordata = get_userdata( $post->post_author );

		$currentday   = false;
		$currentmonth = false;

		$post_date = $post->post_date;
		if ( ! empty( $post_date ) && '0000-00-00 00:00:00' !== $post_date ) {
			// Avoid using mysql2date for performance reasons.
			$currentmonth = substr( $post_date, 5, 2 );
			$day          = substr( $post_date, 8, 2 );
			$year         = substr( $post_date, 2, 2 );

			$currentday = sprintf( '%s.%s.%s', $day, $currentmonth, $year );
		}

		$numpages  = 1;
		$multipage = 0;
		$page      = $this->get( 'page' );
		if ( ! $page ) {
			$page = 1;
		}

		/*
		 * Force full post content when viewing the permalink for the $post,
		 * or when on an RSS feed. Otherwise respect the 'more' tag.
		 */
		if ( get_queried_object_id() === $post->ID && ( $this->is_page() || $this->is_single() ) ) {
			$more = 1;
		} elseif ( $this->is_feed() ) {
			$more = 1;
		} else {
			$more = 0;
		}

		$content = $post->post_content;
		if ( str_contains( $content, '<!--nextpage-->' ) ) {
			$content = str_replace( "\n<!--nextpage-->\n", '<!--nextpage-->', $content );
			$content = str_replace( "\n<!--nextpage-->", '<!--nextpage-->', $content );
			$content = str_replace( "<!--nextpage-->\n", '<!--nextpage-->', $content );

			// Remove the nextpage block delimiters, to avoid invalid block structures in the split content.
			$content = str_replace( '<!-- wp:nextpage -->', '', $content );
			$content = str_replace( '<!-- /wp:nextpage -->', '', $content );

			// Ignore nextpage at the beginning of the content.
			if ( str_starts_with( $content, '<!--nextpage-->' ) ) {
				$content = substr( $content, 15 );
			}

			$pages = explode( '<!--nextpage-->', $content );
		} else {
			$pages = array( $post->post_content );
		}

		/**
		 * Filters the "pages" derived from splitting the post content.
		 *
		 * "Pages" are determined by splitting the post content based on the presence
		 * of `<!-- nextpage -->` tags.
		 *
		 * @since 4.4.0
		 *
		 * @param string[] $pages Array of "pages" from the post content split by `<!-- nextpage -->` tags.
		 * @param WP_Post  $post  Current post object.
		 */
		$pages = apply_filters( 'content_pagination', $pages, $post );

		$numpages = count( $pages );

		if ( $numpages > 1 ) {
			if ( $page > 1 ) {
				$more = 1;
			}
			$multipage = 1;
		} else {
			$multipage = 0;
		}

		$elements = compact( 'id', 'authordata', 'currentday', 'currentmonth', 'page', 'pages', 'multipage', 'more', 'numpages' );

		return $elements;
	}

	/**
	 * Generates cache key.
	 *
	 * @since 6.1.0
	 *
	 * @global wpdb $wpdb WordPress database abstraction object.
	 *
	 * @param array  $args Query arguments.
	 * @param string $sql  SQL statement.
	 * @return string Cache key.
	 */
	protected function generate_cache_key( array $args, $sql ) {
		global $wpdb;

		unset(
			$args['cache_results'],
			$args['fields'],
			$args['lazy_load_term_meta'],
			$args['update_post_meta_cache'],
			$args['update_post_term_cache'],
			$args['update_menu_item_cache'],
			$args['suppress_filters']
		);

		$placeholder = $wpdb->placeholder_escape();
		array_walk_recursive(
			$args,
			/*
			 * Replace wpdb placeholders with the string used in the database
			 * query to avoid unreachable cache keys. This is necessary because
			 * the placeholder is randomly generated in each request.
			 *
			 * $value is passed by reference to allow it to be modified.
			 * array_walk_recursive() does not return an array.
			 */
			static function ( &$value ) use ( $wpdb, $placeholder ) {
				if ( is_string( $value ) && str_contains( $value, $placeholder ) ) {
					$value = $wpdb->remove_placeholder_escape( $value );
				}
			}
		);

		// Replace wpdb placeholder in the SQL statement used by the cache key.
		$sql = $wpdb->remove_placeholder_escape( $sql );
		$key = md5( serialize( $args ) . $sql );

		$last_changed = wp_cache_get_last_changed( 'posts' );
		if ( ! empty( $this->tax_query->queries ) ) {
			$last_changed .= wp_cache_get_last_changed( 'terms' );
		}

		return "wp_query:$key:$last_changed";
	}

	/**
	 * After looping through a nested query, this function
	 * restores the $post global to the current post in this query.
	 *
	 * @since 3.7.0
	 *
	 * @global WP_Post $post Global post object.
	 */
	public function reset_postdata() {
		if ( ! empty( $this->post ) ) {
			$GLOBALS['post'] = $this->post;
			$this->setup_postdata( $this->post );
		}
	}

	/**
	 * Lazyloads term meta for posts in the loop.
	 *
	 * @since 4.4.0
	 * @deprecated 4.5.0 See wp_queue_posts_for_term_meta_lazyload().
	 *
	 * @param mixed $check
	 * @param int   $term_id
	 * @return mixed
	 */
	public function lazyload_term_meta( $check, $term_id ) {
		_deprecated_function( __METHOD__, '4.5.0' );
		return $check;
	}

	/**
	 * Lazyloads comment meta for comments in the loop.
	 *
	 * @since 4.4.0
	 * @deprecated 4.5.0 See wp_lazyload_comment_meta().
	 *
	 * @param mixed $check
	 * @param int   $comment_id
	 * @return mixed
	 */
	public function lazyload_comment_meta( $check, $comment_id ) {
		_deprecated_function( __METHOD__, '4.5.0' );
		return $check;
	}
}