我一直试图玩这里发现的这个骰子计算器：

https://github.com/ringmaster/dicecalc

以前一切都按预期运行,我可以“滚动”3d6,3d6 2,1d12等没有任何问题.

将我的vps升级到带有php7的Ubuntu 16.04之后,我开始收到以下错误：

mod_fcgid: stderr: PHP Fatal error: Uncaught Error: Access to undeclared static property: DiceCalc\CalcOperation::$operators in /public_html/dice/src/DiceCalc/CalcOperation.php:34

我已经对访问未声明的静态属性进行了一些搜索,但无济于事.我试过在每个上面都返回static ::这是它引用的CalcOperation.php：

/**

* Class CalcOperation

*

* @package DiceCalc

* @author Owen Winkler

* @license MIT http://opensource.org/licenses/MIT

*/

namespace DiceCalc;

class CalcOperation {

/**

* @param string $operator

* @param $operand2

* @param $operand1

*

* @throws \Exception

* @return bool|number

*/

public function calc($operator, $operand1, $operand2) {

$operators = array(

'+' => 'add',

'*' => 'multiply',

'=' => 'equalto',

' 'lessthan',

'>' => 'greaterthan',

'^' => 'exponent',

'/' => 'divide',

'-' => 'subtract'

);

if (isset($operators[$operator])) {

return self::$operators[$operator](self::reduce($operand1), self::reduce($operand2));

}

throw new \Exception('Unknown operator "' . $operator . '".');

}

/**

* @param $operand

*

* @return number|string

* @throws \Exception

*/

public function reduce($operand) {

if (is_numeric($operand)) {

return $operand;

} elseif ($operand instanceof Calc) {

return $operand();

}

throw new \Exception('This is not a number');

}

/**

* @param number $operand1

* @param number $operand2

*

* @return bool|number

*/

public function add($operand1, $operand2) {

return $operand1 + $operand2;

}

/**

* @param number $operand1

* @param number $operand2

*

* @return bool|number

*/

public function multiply($operand1, $operand2) {

return $operand1 * $operand2;

}

/**

* @param number $operand1

* @param number $operand2

*

* @return bool|number

*/

public function subtract($operand1, $operand2) {

return $operand1 - $operand2;

}

/**

* @param number $operand1

* @param number $operand2

*

* @return bool|number

*/

public function divide($operand1, $operand2) {

return $operand1 / $operand2;

}

/**

* @param number $operand1

* @param number $operand2

*

* @return bool|number

*/

public function exponent($operand1, $operand2) {

return pow($operand1, $operand2);

}

/**

* @param number $operand1

* @param number $operand2

*

* @return bool

*/

public function greaterthan($operand1, $operand2) {

return $operand1 > $operand2;

}

/**

* @param number $operand1

* @param number $operand2

*

* @return bool

*/

public function lessthan($operand1, $operand2) {

return ($operand1 < $operand2);

}

/**

* @param number $operand1

* @param number $operand2

*

* @return bool

*/

public function equalto($operand1, $operand2) {

return ($operand1 == $operand2);

}

}

这是调用类的行：

$stack[] = CalcOperation::calc($step, $r2, $r1);

我刚刚开始围绕课程等等,所以我不知道如何解决这个问题.我已经尝试切换返回self ::返回static ::在我通过搜索这里找到的其他一些东西.我现在才被困住了.有人能帮忙吗？