Your examples provide code for checking the existance of real
properties. But how to check existance of a magic one?
The best is currently __isset(), but to comply with isset() definition,
it should not return true when the magic property has null value, thus I
belive, there is currently not way (provided by php language) to check
for existance of magic property.
With kind regards / Mit freundlichen Grüßen / S přátelským pozdravem,
Michael Voříšek
On 4 Sep 2020 19:23, Marco Pivetta wrote:
Heya,
On Fri, Sep 4, 2020 at 7:03 PM Michael Voříšek - ČVUT FEL <voris...@fel.cvut.cz> wrote:
isset() returns false for null
__isset() should return the same, but then if magic property with null
value exists, there is no way to detect it
Example: https://3v4l.org/GqUsh
this is currently an limitation of php
Ideally, we should introduce __exist() which should return true even if
value is null and for BC autoimplement __isset() based on it and __get,
ie.
function __isset($n) { return $this->__exist($n) && $this->__isset($n)
!== null; }
I'd endorse **NOT** checking for property existence on objects that don't have a clearly defined interface/type: that's something for a static analyzer, not (usually) for runtime code.
If you still need to do that (anti-patterns such as stuffing things in `stdClass` instances), checking if a property is defined is trivial with reflection:
```php
<?php
class SomethingMagicAndTerriblyUgly
{
public $foo = null;
private $bar = null;
}
var_dump((new
ReflectionClass(SomethingMagicAndTerriblyUgly::class))->hasProperty('foo'));
var_dump((new
ReflectionClass(SomethingMagicAndTerriblyUgly::class))->hasProperty('bar'));
var_dump((new ReflectionClass(SomethingMagicAndTerriblyUgly::class))->hasProperty('baz'));
```
https://3v4l.org/pVC4j
Checking if a **public** property exists at runtime is done via `array_key_exists()`, not via `isset()`:
```php
<?php
class SomethingMagicAndTerriblyUgly
{
public $foo = null;
private $bar = null;
}
var_dump(array_key_exists('foo', (array) (new SomethingMagicAndTerriblyUgly)));
var_dump(array_key_exists('bar', (array) (new SomethingMagicAndTerriblyUgly)));
```
https://3v4l.org/ZLSjq
Marco Pivetta
http://twitter.com/Ocramius
http://ocramius.github.com/
