Re: In php 8.0: unable to distinguish between instance variable beingnull and unset

Emiel Mols wrote on 9/3/21 07:08:
> 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
> <https://github.com/php/php-src/blob/a13730c5e465b3c349a7970d15a49e4e132d4e07/Zend/zend_builtin_functions.c#L943>
> .
> 
> Apart from using debug_zval_dump (too expensive), any hints? This feels
> like quite the oversight honestly :).
> 
> Best,
> 
> Emiel
> 

If you use `public int $v`, there shouldn't be a way to set it `null`,
unless I'm missing something.

https://3v4l.org/nNDq4

Cheers,
Ben

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