Flow\Template::displayParent PHP Method

    public function displayParent($name, $context, $blocks, $macros, $imports)
    {
        $parent = $this;
        while ($parent = $parent->parent) {
            if (isset($parent->blocks[$name]) && is_callable($parent->blocks[$name])) {
                return call_user_func($parent->blocks[$name], $context, $blocks, $macros, $imports);
            }
        }
    }