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function is not described

_navigation_markup() WP 4.1.0

Wraps passed links in navigational markup.

Hooks in function
Return

String. Navigation template tag.

Usage

_navigation_markup( $links, $class, $screen_reader_text );
$links(string) (required)
Navigational links.
$class(string)
Custom class for nav element. Default: 'posts-navigation'.
Default: 'posts-navigation'
$screen_reader_text(string)
Screen reader text for nav element. Default: 'Posts navigation'.
Default: ''

Code of navigation markup: wp-includes/link-template.php WP 5.2.1

<?php
function _navigation_markup( $links, $class = 'posts-navigation', $screen_reader_text = '' ) {
	if ( empty( $screen_reader_text ) ) {
		$screen_reader_text = __( 'Posts navigation' );
	}

	$template = '
	<nav class="navigation %1$s" role="navigation">
		<h2 class="screen-reader-text">%2$s</h2>
		<div class="nav-links">%3$s</div>
	</nav>';

	/**
	 * Filters the navigation markup template.
	 *
	 * Note: The filtered template HTML must contain specifiers for the navigation
	 * class (%1$s), the screen-reader-text value (%2$s), and placement of the
	 * navigation links (%3$s):
	 *
	 *     <nav class="navigation %1$s" role="navigation">
	 *         <h2 class="screen-reader-text">%2$s</h2>
	 *         <div class="nav-links">%3$s</div>
	 *     </nav>
	 *
	 * @since 4.4.0
	 *
	 * @param string $template The default template.
	 * @param string $class    The class passed by the calling function.
	 * @return string Navigation template.
	 */
	$template = apply_filters( 'navigation_markup_template', $template, $class );

	return sprintf( $template, sanitize_html_class( $class ), esc_html( $screen_reader_text ), $links );
}