FluidXml\FluidXml::chooseContext PHP Méthode

    protected function chooseContext(\Closure $fn)
    {
        // If the user has requested ['root' => null] at construction time
        // 'context()' promotes DOMDocument as root node.
        $context = $this->context();
        $new_context = $fn($context);
        if ($context !== $new_context) {
            // If the two contextes are diffent, the user has requested
            // a switch of the context and we have to return it.
            return $new_context;
        }
        return $this;
    }