public static function getVariableValues(Schema $schema, array $asts, array $inputs)
    {
        $values = [];
        foreach ($asts as $ast) {
            $variable = $ast->get('variable')->get('name')->get('value');
            $values[$variable] = self::getvariableValue($schema, $ast, isset($inputs[$variable]) ? $inputs[$variable] : NULL);
        }
        return $values;
    }