mment', 'export'.
	 */
	echo apply_filters( 'the_generator', get_the_generator( $type ), $type ) . "\n";
}

/**
 * Creates the generator XML or Comment for RSS, ATOM, etc.
 *
 * Returns the correct generator type for the requested output format. Allows
 * for a plugin to filter generators on an individual basis using the
 * {@see 'get_the_generator_$type'} filter.
 *
 * @since 2.5.0
 *
 * @param string $type The type of generator to return - (html|xhtml|atom|rss2|rdf|comment|export).
 * @return string|void The HTML content for the generator.
 */
function get_the_generator( $type = '' ) {
	if ( empty( $type ) ) {

		$current_filter = current_filter();
		if ( empty( $current_filter ) ) {
			return;
		}

		switch ( $current_filter ) {
			case 'rss2_head':
			case 'commentsrss2_head':
				$type = 'rss2';
				break;
			case 'rss_head':
			case 'opml_head':
				$type = 'comment';
				break;
			case 'rdf_header':
				$type = 'rdf';
				break;
			case 'atom_head':
			case 'comments_atom_head':
			case 'app_head':
				$type = 'atom';
				break;
		}
	}

	switch ( $type ) {
		case 'html':
			$gen = '<meta name="generator" content="WordPress ' . esc_attr( get_bloginfo( 'version' ) ) . '">';
			break;
		case 'xhtml':
			$gen = '<meta name="generator" content="WordPress ' . esc_attr( get_bloginfo( 'version' ) ) . '" />';
			break;
		case 'atom':
			$gen = '<generator uri="https://wordpress.org/" version="' . esc_attr( get_bloginfo_rss( 'version' ) ) . '">WordPress</generator>';
			break;
		case 'rss2':
			$gen = '<generator>' . esc_url_raw( 'https://wordpress.org/?v=' . get_bloginfo_rss( 'version' ) ) . '</generator>';
			break;
		case 'rdf':
			$gen = '<admin:generatorAgent rdf:resource="' . esc_url_raw( 'https://wordpress.org/?v=' . get_bloginfo_rss( 'version' ) ) . '" />';
			break;
		case 'comment':
			$gen = '<!-- generator="WordPress/' . esc_attr( get_bloginfo( 'version' ) ) . '" -->';
			break;
		case 'export':
			$gen = '<!-- generator="WordPress/' . esc_attr( get_bloginfo_rss( 'version' ) ) . '" created="' . gmdate( 'Y-m-d H:i' ) . '" -->';
			break;
	}

	/**
	 * Filters the HTML for the retrieved generator type.
	 *
	 * The dynamic portion of the hook name, `$type`, refers to the generator type.
	 *
	 * @since 2.5.0
	 *
	 * @param string $gen  The HTML markup output to wp_head().
	 * @param string $type The type of generator. Accepts 'html', 'xhtml', 'atom',
	 *                     'rss2', 'rdf', 'comment', 'export'.
	 */
	return apply_filters( "get_the_generator_{$type}", $gen, $type );
}

/**
 * Outputs the HTML checked attribute.
 *
 * Compares the first two arguments and if identical marks as checked
 *
 * @since 1.0.0
 *
 * @param mixed $checked One of the values to compare
 * @param mixed $current (true) The other value to compare if not just true
 * @param bool  $echo    Whether to echo or just return the string
 * @return string HTML attribute or empty string
 */
function checked( $checked, $current = true, $echo = true ) {
	return __checked_selected_helper( $checked, $current, $echo, 'checked' );
}

/**
 * Outputs the HTML selected attribute.
 *
 * Compares the first two arguments and if identical marks as selected
 *
 * @since 1.0.0
 *
 * @param mixed $selected One of the values to compare
 * @param mixed $current  (true) The other value to compare if not just true
 * @param bool  $echo     Whether to echo or just return the string
 * @return string HTML attribute or empty string
 */
function selected( $selected, $current = true, $echo = true ) {
	return __checked_selected_helper( $selected, $current, $echo, 'selected' );
}

/**
 * Outputs the HTML disabled attribute.
 *
 * Compares the first two arguments and if identical marks as disabled
 *
 * @since 3.0.0
 *
 * @param mixed $disabled One of the values to compare
 * @param mixed $current  (true) The other value to compare if not just true
 * @param bool  $echo     Whether to echo or just return the string
 * @return string HTML attribute or empty string
 */
function disabled( $disabled, $current = true, $echo = true ) {
	return __checked_selected_helper( $disabled, $current, $echo, 'disabled' );
}

/**
 * Outputs the HTML readonly attribute.
 *
 * Compares the first two arguments and if identical marks as readonly
 *
 * @since 4.9.0
 *
 * @param mixed $readonly One of the values to compare
 * @param mixed $current  (true) The other value to compare if not just true
 * @param bool  $echo     Whether to echo or just return the string
 * @return string HTML attribute or empty string
 */
function readonly( $readonly, $current = true, $echo = true ) {
	return __checked_selected_helper( $readonly, $current, $echo, 'readonly' );
}

/**
 * Private helper function for checked, selected, disabled and readonly.
 *
 * Compares the first two arguments and if identical marks as $type
 *
 * @since 2.8.0
 * @access private
 *
 * @param mixed  $helper  One of the values to compare
 * @param mixed  $current (true) The other value to compare if not just true
 * @param bool   $echo    Whether to echo or just return the string
 * @param string $type    The type of checked|selected|disabled|readonly we are doing
 * @return string HTML attribute or empty string
 */
function __checked_selected_helper( $helper, $current, $echo, $type ) { // phpcs:ignore WordPress.NamingConventions.ValidFunctionName.FunctionDoubleUnderscore,PHPCompatibility.FunctionNameRestrictions.ReservedFunctionNames.FunctionDoubleUnderscore
	if ( (string) $helper === (string) $current ) {
		$result = " $type='$type'";
	} else {
		$result = '';
	}

	if ( $echo ) {
		echo $result;
	}

	return $result;
}

/**
 * Default settings for heartbeat
 *
 * Outputs the nonce used in the heartbeat XHR
 *
 * @since 3.6.0
 *
 * @param array $settings
 * @return array Heartbeat settings.
 */
function wp_heartbeat_settings( $settings ) {
	if ( ! is_admin() ) {
		$settings['ajaxurl'] = admin_url( 'admin-ajax.php', 'relative' );
	}

	if ( is_user_logged_in() ) {
		$settings['nonce'] = wp_create_nonce( 'heartbeat-nonce' );
	}

	return $settings;
}