Re: Validating #[\Attribute] targets

> Le 25 juil. 2025 à 18:37, Daniel Scherzer <daniel.e.scherzer@gmail.com> a écrit : >  > Hi internals, > > The #[\Attribute] attribute is used to mark classes as being usable as attributes. It currently > does not trigger any error if added to a trait, interface, enum, or abstract class. However, if any > of those *were* used as an attribute, calling ReflectionAttribute::newInstance() would fail; if you > are not going to call ReflectionAttribute::newInstance(), then you don't really need to mark > the trait/interface/enum/abstract class as an attribute. > > I have proposed https://github.com/php/php-src/pull/19154 to > add validation to the #[Attribute] attribute, and it was suggested that I post here on the mailing > list in case there were any objections. So, are there? > > -Daniel Hi, Validating more precisely the target of #[Atrribute] is reasonable. Now, observing that there are several internal attributes that may benefit this capability (e.g. #[Attribute], #[AllowDynamicProperties], #[Deprecated] on traits as currenty voted on), I wonder if we can also expose this capability to user-defined attributes? Concretely, there could be the following additional constants: * Attribute::TARGET_INTERFACE * Attribute::TARGET_ABSTRACT_CLASS * Attribute::TARGET_TRAIT * Attribute::TARGET_ENUM * Attribute::TARGET_REGULAR_CLASS and Attribute::TARGET_CLASS would be equal to the result of combining all of those with the | operator. —Claude —Claude