Will isset() trigger __get and why?

Question

class a {
   function __get($property){...}
}

$obj = new a();
var_dump(isset($obj->newproperty));

Seems the answer is nope but why?

Answer 1

The magic function __get is only called when you try to access a property that doesn't exist. Checking whether a property exists is not the same as retrieving it.