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filter is not described

wp_edit_nav_menu_walker filter-hook . WP 3.0.0

Filters the Walker class used when adding nav menu items.

Usage

add_filter( 'wp_edit_nav_menu_walker', 'filter_function_name_3258', 10, 2 );
function filter_function_name_3258( $class, $menu_id ){
	// filter...

	return $class;
}
$class(string)
The walker class to use.
Default: 'Walker_Nav_Menu_Edit'
$menu_id(int)
ID of the menu being rendered.

Where the hook is called

wp_get_nav_menu_to_edit()
wp_ajax_add_menu_item()
wp-admin/includes/nav-menu.php 931
$walker_class_name = apply_filters( 'wp_edit_nav_menu_walker', 'Walker_Nav_Menu_Edit', $menu_id );
wp-admin/includes/ajax-actions.php 1263
$walker_class_name = apply_filters( 'wp_edit_nav_menu_walker', 'Walker_Nav_Menu_Edit', $_POST['menu'] );

Where the hook is used (in WP core)

Does not used.