Question

I have a function a. That is re used in many times without any problem. But now i cant call the function.This is my function

function a($a,&$b){
        // functions code here
        }

I calling function a like this.

a(3,null);

Whats the error with my code?

Answer 1

You’ll see that you get an error message along the lines of

PHP Fatal error:  Only variables can be passed by reference in SOMETHING.php on line xxx

This is because your function is saying that its second parameter is a reference (i.e. &$b) and this requires that you pass a variable. You are actually passing null which is not a variable, hence the problem.

If you require the second parameter as a reference (and one way of fixing this might be to remove that requirement) pass along a variable that is set to null. E.g.

$c = null;
a(3, $c);