Variable watch in PHP

Question

Does PHP have the ability to watch a variable (or object property) and run a function when its value changes, similar to Javascript's watch function?

Answer 1

XDebug might have this, but I don't know for sure.

If you're trying to debug a member variable on an object, you can use overloading:

public function __set($var, $val)
{
    if ($var == 'interesting') {
        echo "$var set to: ";
        var_dump($val);
    }
    $this->$var = $val;
}

Answer 2

This would be possible when using XDebug along side an IDE like eclipse.