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Date: Mon, 20 Apr 2026 14:54:29 +0300
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Subject: Re: [PHP-DEV] [IDEA for RFC] class_uses and optionally returning
 traits for parent classes
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From: arokettu@outlook.com (Anton Smirnov)

On 20/04/2026 12:32, Claude Pache wrote:
> I think that `class_uses()` should never have been implemented, because 
> it gives a false sense of symmetry with `class_implements()` and 
> `class_parents()`. Implemented interfaces and parent classes can be used 
> as types on the corresponding object (and types are inherited), while 
> used traits cannot. Those are fundamentally different concepts.

I agree

> If, for some reason, you want to “cheat” and use traits as if they were 
> inherited types, you are free to do that, but I don’t think that PHP 
> should provide a built-in function that goes beyond what traits are 
> intended for.
That won't even work reliably. You can rename trait methods and override 
them with methods with incompatible signatures and do other similar 
stuff to make this use case a nightmare.

Therefore this:

 >> and then where needed checking for the existence of
 >> the trait to tell if the functionality is supported or not (think
 >> along the lines of if a trait could implement an interface).

is totally impossible to do. A trait with a method does not guarantee 
you that the method is available.

Anton