Class X uses generic trait Y but does not specify its types: T

[rkrx]

How do I notate use Y when Y is a generic trait?

https://phpstan.org/r/79dfb460-43b4-4d8d-9972-d2bde68891dd

<?php declare(strict_types = 1);

/** @template T */
class Z {
	/**
	 * @param callable(): T $callbackFn
	 */
	public function __construct(callable $callbackFn) { $callbackFn(); }
}

/** @template T */
trait Y {
	/**
	 * @param callable(): T $callbackFn
	 * @return Z<T>
	 */
	public function create(callable $callbackFn): Z {
		return new Z($callbackFn);
	}
}

class X {
	use Y;
	// Class X uses generic trait Y but does not specify its types: T
}

[ondrejmirtes]

Hi, with the help of @use: https://phpstan.org/r/bdedc5ee-8113-430a-9ab3-64d13ee5bc47

[ondrejmirtes]

Which is an equivalent for @implements and @extends that solve the same situations with parent classes and implemented interfaces :)

[rkrx]

@ondrejmirtes Awesome, thank you!

[tylercollier]

Just to help the next person, the @use goes on the use, not on the class. It's in the link from ondrejmirtes but for convenience I'll paste it:

<?php declare(strict_types = 1);

/** @template T */
class Z {
	/**
	 * @param callable(): T $callbackFn
	 */
	public function __construct(callable $callbackFn) { $callbackFn(); }
}

/** @template T */
trait Y {
	/**
	 * @param callable(): T $callbackFn
	 * @return Z<T>
	 */
	public function create(callable $callbackFn): Z {
		return new Z($callbackFn);
	}
}

class X {
	/** @use Y<\stdClass> */
	use Y;
}