public function addExpression(string $privilegeIdentifier, string $expression): void
    {
        $functionName = $this->generateExpressionFunctionName($privilegeIdentifier);
        $wrappedExpression = 'return ' . $expression . ';';
        $this->runtimeExpressionsCache->set($functionName, $wrappedExpression);
        $this->runtimeExpressions[$functionName] = eval($wrappedExpression);
    }