walk_category_tree() WordPress Function

The walk_category_tree() function is a recursive function used to list categories in a hierarchy. It accepts a callback function as an argument, which is used to list the categories. The callback function is called for each category in the hierarchy, and is passed the category object, the category's depth in the hierarchy, and the current walker object.

walk_category_tree( mixed $args ) #

function walk_category_tree( ...$args ) {
	// The user's options are the third parameter.
	if ( empty( $args[2]['walker'] ) || ! ( $args[2]['walker'] instanceof Walker ) ) {
		$walker = new Walker_Category;
	} else {
		/**
		 * @var Walker $walker
		 */
		$walker = $args[2]['walker'];
	}
	return $walker->walk( ...$args );
}