PHP Error : Fatal error: Constant expression contains invalid operations

User 1: Hi there,

I've encountered a similar error before and I think I might have a solution for you. The error message "Constant expression contains invalid operations" usually occurs when you try to perform a non-static operation or use a non-constant value inside a constant expression.

In your case, the error is caused by using the multiplication operator (*) inside the constant expression. PHP can only evaluate constant expressions during compilation, and the result must be a simple value like a number, string, or boolean.

To overcome this error, you can try replacing the constant expression with a variable expression. Here's an updated version of your code:

php
class MyClass {

    const MY_CONSTANT = 5;



    public function myFunction() {

        $myVariable = 10;

        $constantExpression = self::MY_CONSTANT * 2;



        if ($myVariable > $constantExpression) {

            // Some code here

        }

    }

}

User 2: Hey there,

I completely understand the frustration and confusion caused by this error. I faced a similar issue a while ago, and it took me some time to figure out the root cause. Let me share my experience with you.

The error message "Constant expression contains invalid operations" is mostly triggered when you use an incorrect operation within a constant expression. In your case, it seems like you're attempting to perform a mathematical operation using the multiplication operator (*) inside the constant expression.

To overcome this error, one possible solution is to use a different approach. Instead of using a constant expression, you can define a static variable inside your class and assign the result of the multiplication to it. Here's an example based on your code:

php
class MyClass {

    const MY_CONSTANT = 5;

    static $constantExpression;



    public function myFunction() {

        $myVariable = 10;



        self::$constantExpression = self::MY_CONSTANT * 2;



        if ($myVariable > self::$constantExpression) {

            // Some code here

        }

    }

}

More Topics Related to PHP

• What are the recommended PHP versions for different operating systems?
• Can I install PHP without root/administrator access?
• How can I verify the integrity of the PHP installation files?
• Are there any specific considerations when installing PHP on a shared hosting environment?
• Is it possible to install PHP alongside other programming languages like Python or Ruby?

More Topics Related to PHP Code

• Are there any specific optimizations or performance tweaks for PHP installations on macOS?
• How can I integrate PHP with macOS-specific technologies like Core Data or Apple Push Notification Service (APNs)?
• I'm getting an "Internal Server Error" when accessing PHP files. What are the possible causes and how can I troubleshoot this error?
• What is the purpose of the opening <?php tag?
• Can I use whitespace and indentation freely in PHP code?

More Topics Related to Expertise

• How can I scale PHP applications in the cloud to handle high traffic or load balancing?
• Notice: Undefined variable: mine in C:\wamp\www\social\profile-view.php on line 58
• php - PhpStorm: extract() identifying variables
• PHP regular expression string starting with certain characters and followed by digits
• PHP Error : Fatal error: Constant expression contains invalid operations