Re: [PHP-DEV] [RFC] [Discussion] Add ReflectionAttribute::getCurrent()

[Tim Düsterhus]

Hi

Am 2026-05-16 16:22, schrieb Daniel Scherzer:
[…]

Okay, fair enough. I can see how running code for additional validation 
can be useful and just the targets themselves are insufficient. This 
would also make sense to align the capabilities of internal code and 
userland code.

I would then suggest putting the extra validation where the existing 
validation is: Namely into the #[\Attribute] attribute. Closures and 
first class callables are supported in attributes since PHP 8.5 and 
would allow for a very straight-forward solution that keeps the 
attribute itself “pure metadata” in a value object.

    <?php

    #[Attribute]
    final class MyAttribute {
        public function __construct(
            public int $target,
            public Closure $validate,
        ) { }
    }

    #[MyAttribute(Attribute::TARGET_METHOD|Attribute::TARGET_FUNCTION, 
MyNoDiscard::validate(...))]
    final class MyNoDiscard
    {
        public readonly ?string $message;

        public function __construct(?string $message = null) { }

        private static function 
validate(ReflectionMethod|ReflectionFunction $f) {
            if ($f instanceof ReflectionMethod) {
                if ($f->getName()[0] === '$') {
                    throw new Error('May not on property hooks');
                }
            }
        }
    }

    class X {
        public string $x {
            #[MyNoDiscard]
            get { return 'x'; }
        }
    }

    $r = new ReflectionClass(MyNoDiscard::class);
    $validator = $r->getAttributes()[0]->newInstance()->validate;

    $r = new ReflectionClass(X::class);
    $h = $r->getProperty('x')->getHook(PropertyHookType::Get);

    $validator($h); // Throws

Best regards
Tim Düsterhus