On Thu, 9 Jan 2020 at 15:22, Andreas Hennings <[email protected]> wrote:
> > However, $this is not a real type, and it is unclear what the advantage
> of specifying $this rather than static would be from a type system level
> perspective.
>
> Perhaps not from a "type system level", but from a more broad "enforced
> contract" level.
> E.g. IDEs or code inspection tools can warn if a method will not return
> $this.
> This also means recursive calls also need to return $this instead of
> static.
>
> class C {
> function foo(): static {
> return clone $this;
> }
> function bar(): $this {
> return $this->foo(); // IDE can complain.
> }
> }
>
Of course this ": $this" could be added later in the future.
But this would have the risk that people start adding ": static" on methods
that really return $this.
This would cause confusion if later some packages introduce ": $this", but
others are still behind.
namespace oldpackage;
class B {
function foo(): static { // Actually returns $this, not just static.
return $this;
}
}
namespace newpackage;
class C extends B {
function foo(): $this {
return parent::foo(); // Should the IDE complain?
}
}
>
>
> On Thu, 9 Jan 2020 at 15:07, Larry Garfield <[email protected]>
> wrote:
>
>> On Wed, Jan 8, 2020, at 5:42 AM, Nikita Popov wrote:
>> > Hi internals,
>> >
>> > I would like to propose the following RFC, which allows using "static"
>> as a
>> > return type:
>> >
>> > https://wiki.php.net/rfc/static_return_type
>> >
>> > While I'm personally not a fan of late static binding, we do support it
>> and
>> > people do use it quite heavily, so I think we should also support it in
>> > return types.
>> >
>> > Regards,
>> > Nikita
>>
>>
>> Is "squee!" an appropriate response on the list? For interface authors
>> this is a huge deal.
>>
>> --Larry Garfield
>>
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>>
