Pour un client particulier, Deefuse a eu besoin de développer un Walker spécial pour un menu. L’idée est que ce Walker ne va pas afficher le menu courant. Nous aurions pu le faire en css pure, mais voici la manip à faire pour le faire grace à un Walker personnalisé : Je vous donne ici la classe complète du Walker. Ce Walker WordPress ne va pas afficher l’élément <li> si celui-ci contient la class current-menu-item ou bien alors current-menu-ancestor

class Exclude_current_menu_walker extends Walker_Nav_Menu{
    public function start_el( &$output, $item, $depth = 0, $args = array(), $id = 0 ) {
        $indent = ( $depth ) ? str_repeat( "\t", $depth ) : '';
 
        $classes = empty( $item->classes ) ? array() : (array) $item->classes;
        $classes[] = 'menu-item-' . $item->ID;
 
        $current_menu_item = in_array("current-menu-item", $classes);
        $current_page_ancestor = in_array("current-page-ancestor", $classes);
        /**
         * Filter the CSS class(es) applied to a menu item's list item element.
         *
         * @since 3.0.0
         * @since 4.1.0 The `$depth` parameter was added.
         *
         * @param array  $classes The CSS classes that are applied to the menu item's `` element.
         * @param object $item    The current menu item.
         * @param array  $args    An array of {@see wp_nav_menu()} arguments.
         * @param int    $depth   Depth of menu item. Used for padding.
         */
        $class_names = join( ' ', apply_filters( 'nav_menu_css_class', array_filter( $classes ), $item, $args, $depth ) );
        $class_names = $class_names ? ' class="' . esc_attr( $class_names ) . '"' : '';
 
        /**
         * Filter the ID applied to a menu item's list item element.
         *
         * @since 3.0.1
         * @since 4.1.0 The `$depth` parameter was added.
         *
         * @param string $menu_id The ID that is applied to the menu item's `` element.
         * @param object $item    The current menu item.
         * @param array  $args    An array of {@see wp_nav_menu()} arguments.
         * @param int    $depth   Depth of menu item. Used for padding.
         */
        $id = apply_filters( 'nav_menu_item_id', 'menu-item-'. $item->ID, $item, $args, $depth );
        $id = $id ? ' id="' . esc_attr( $id ) . '"' : '';
 
 
        if(!$current_menu_item && !$current_page_ancestor)
        $output .= $indent . '';
 
        $atts = array();
        $atts['title']  = ! empty( $item->attr_title ) ? $item->attr_title : '';
        $atts['target'] = ! empty( $item->target )     ? $item->target     : '';
        $atts['rel']    = ! empty( $item->xfn )        ? $item->xfn        : '';
        $atts['href']   = ! empty( $item->url )        ? $item->url        : '';
 
        /**
         * Filter the HTML attributes applied to a menu item's anchor element.
         *
         * @since 3.6.0
         * @since 4.1.0 The `$depth` parameter was added.
         *
         * @param array $atts {
         *     The HTML attributes applied to the menu item's `` element, empty strings are ignored.
         *
         *     @type string $title  Title attribute.
         *     @type string $target Target attribute.
         *     @type string $rel    The rel attribute.
         *     @type string $href   The href attribute.
         * }
         * @param object $item  The current menu item.
         * @param array  $args  An array of {@see wp_nav_menu()} arguments.
         * @param int    $depth Depth of menu item. Used for padding.
         */
        $atts = apply_filters( 'nav_menu_link_attributes', $atts, $item, $args, $depth );
 
        $attributes = '';
        foreach ( $atts as $attr => $value ) {
            if ( ! empty( $value ) ) {
                $value = ( 'href' === $attr ) ? esc_url( $value ) : esc_attr( $value );
                $attributes .= ' ' . $attr . '="' . $value . '"';
            }
        }
 
        $item_output = $args->before;
        $item_output .= '';
 
 
        /** This filter is documented in wp-includes/post-template.php */
        $item_output .= $args->link_before . apply_filters( 'the_title', $item->title, $item->ID ) . $args->link_after;
 
        $item_output .= '';
        $item_output .= $args->after;
 
        /**
         * Filter a menu item's starting output.
         *
         * The menu item's starting output only includes `$args->before`, the opening ``,
         * the menu item's title, the closing ``, and `$args->after`. Currently, there is
         * no filter for modifying the opening and closing `` for a menu item.
         *
         * @since 3.0.0
         *
         * @param string $item_output The menu item's starting HTML output.
         * @param object $item        Menu item data object.
         * @param int    $depth       Depth of menu item. Used for padding.
         * @param array  $args        An array of {@see wp_nav_menu()} arguments.
         */
        if(!$current_menu_item && !$current_page_ancestor)
        $output .= apply_filters( 'walker_nav_menu_start_el', $item_output, $item, $depth, $args );
    }
 
    /**
     * Ends the element output, if needed.
     *
     * @see Walker::end_el()
     *
     * @since 3.0.0
     *
     * @param string $output Passed by reference. Used to append additional content.
     * @param object $item   Page data object. Not used.
     * @param int    $depth  Depth of page. Not Used.
     * @param array  $args   An array of arguments. @see wp_nav_menu()
     */
    public function end_el( &$output, $item, $depth = 0, $args = array() ) {
        $classes = empty( $item->classes ) ? array() : (array) $item->classes;
        $classes[] = 'menu-item-' . $item->ID;
 
        $current_menu_item = in_array("current-menu-item", $classes);
        $current_page_ancestor = in_array("current-page-ancestor", $classes);
 
        if(!$current_menu_item && !$current_page_ancestor)
        $output .= "\n";
    }
}

Pour appeler votre Walker, faites comme d’habitude :

wp_nav_menu(array(
       'theme_location'  => '...',
       'walker'         => new Exlude_current_menu_walker()
   ));