public function shift()
    {
        $this->throwExceptionIfEmpty();

        $arrayCopy = $this->getArrayCopy();
        $firstElement = array_shift($arrayCopy);
        $this->exchangeArray($arrayCopy);
        return $firstElement;
    }
public function shift()
    {
        $this->throwExceptionIfEmpty();

        $arrayCopy = $this->getArrayCopy();
        $firstElement = array_shift($arrayCopy);
        $this->exchangeArray($arrayCopy);
        return $firstElement;
    }
public function shift ( ) { $ this -> throwExceptionIfEmpty ( ) ; $ arrayCopy = $ this -> getArrayCopy ( ) ; $ firstElement = array_shift ( $ arrayCopy ) ; $ this -> exchangeArray ( $ arrayCopy ) ; return $ firstElement ; }
Shift an element off the beginning of array
@return mixed
Shift an element off the beginning of array