public function returns($returns)
    {
        //check if the Return clause is even supported
        $returnTypes = $this->getValidReturnTypes();
        if (count($returnTypes) <= 0) {
            throw new LogicException("Return clause not supported for this statement");
        }

        $returns = strtoupper($returns);
        if (!in_array($returns, $returnTypes)) {
            throw new LogicException(sprintf("Unknown return type %s", $returns));
        }
        $this->setToken('Returns', $returns);
    }