What is * mean in xdebug?

  laravel, php, xdebug

I’m trying to creat custom Error class in laravel. When I’m running throug xdebug i see such values in it *Exception*string, *Exception*trace and *Exception*previous. What this ** means and name between it. I thought, that it’s class name, where this variables define and not redefined in another place. I created custom classes and extend one from another. Then define variable in parent class and ran throug xdebug. As the result i got nothing.

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Source: Ask PHP