public function fromWp(\WP_Error $WP_Error): CoreClasses\Core\Error
    {
        $Error = $this->c::error();

        foreach ($WP_Error->errors as $_code => $_messages) {
            $_slug = $this->c::nameToSlug($_code);
            $_data = $WP_Error->error_data[$_code] ?? null;

            foreach ($_messages as $_message) {
                $Error->add($_slug, $_message, $_data);
            } // unset($_message); // Housekeeping.
        } // unset($_code, $_messages, $_slug, $_data); // Housekeeping.

        return $Error;
    }