Hello,
Our codebase depends on distinguishing whether an instance variable is unset, or simply null:
class C { public int $v = 123; }
$x = new C; unset($x->v);
$y = new C; $u->v = null;
In php <8.0 we made this work with @array_key_exists($x, 'v'), which stopped working. isset($x->x) doesn't work, as it will return true for 'null' as well. property_exists($x, 'v') will always return true as long as the variable is declared: php-src here.
Apart from using debug_zval_dump (too expensive), any hints? This feels like quite the oversight honestly :).
Best,
Emiel
