>
> What's the advantage of a language construct over the following?
>
> ```php
> /**
> * @template T of object
> * @psalm-assert T $value
> * @param class-string<T> $type
> */
> function as(mixed $value, string $type): mixed
> {
> if (! $value instanceof $type) { throw
> SomeKindOfException::forMismatchingRequirements($value, $type); }
>
> return $value;
> }
>
> echo as(myExpression(), MyType::class)->methodOfMyType();
> ```
>
>
A static analysis tool supporting something in docblocks should not
preclude those things being added in syntax IMO.
Hack's `as` operator is very neat, and it'd be trivial for existing SA
tools to support the same in PHP.
Here's a demo of `as` in Hack getting flagged by a SA tool:
https://hakana.dev/#XQAAgAA2AAAAAAAAAAAzHUn_qWH7EwabJzyN0tdfxv3ug6f7oZ-qScnamcl1qjUZCPmuKA3tD-KFr1f0ZPcrAXt_D1L___KsQAA%3D
This would also benefit from a `nonnull` subtype of `mixed` which could be
used as a null refinement.
