Hi Nikita, I checked the Union Type implementation, and it more or less good. I mean, it implements the RFC in almost the best way. However, as I don't like the RFC itself. Especially, unions of multiple classes and interference with type variance, I'll vote against this.
Actually, I think PHP already took wrong direction implementing "typed references" and "type variance". Introducing more "typing", we suggest using it, but this "typing" comes with a huge cost of run-time checks. >From 10% (scalar type hint of argument) to 3 times (typed reference >assignment) performance degradation. Anyone may rerun my benchmarks https://gist.github.com/dstogov/fb32023e8dd55e58312ae0e5029556a9 Thanks. Dmitry. ________________________________ From: Dmitry Stogov <dmi...@zend.com> Sent: Tuesday, October 22, 2019 15:38 To: Nikita Popov <nikita....@gmail.com>; PHP internals <internals@lists.php.net> Subject: Re: [PHP-DEV] Re: [RFC] Union Types v2 Hi Nikita, Can you please give me one/two days, before starting the voting, for implementation review (at least until October 25), Thanks. Dmitry. ________________________________ From: Nikita Popov <nikita....@gmail.com> Sent: Tuesday, October 22, 2019 12:36 To: PHP internals <internals@lists.php.net> Subject: [PHP-DEV] Re: [RFC] Union Types v2 On Wed, Sep 4, 2019 at 10:26 AM Nikita Popov <nikita....@gmail.com> wrote: > Hi internals, > > I'd like to start the discussion on union types again, with a new proposal: > > Pull Request: https://github.com/php/php-rfcs/pull/1 > Rendered Proposal: > https://github.com/nikic/php-rfcs/blob/union-types/rfcs/0000-union-types-v2.md > > As an experiment, I'm submitting this RFC as a GitHub pull request, to > evaluate whether this might be a better medium for RFC proposals in the > future. It would be great if we could keep the discussion to the GitHub > pull request for the purpose of this experiment (keep in mind that you can > also create comments on specific lines in the proposal, not just the > overall discussion thread!) Of course, you can also reply to this mail > instead. The final vote will be held in the wiki as usual. > > Relatively to the previous proposal by Bob&Levi ( > https://wiki.php.net/rfc/union_types), I think the main differences in > this proposal are: > * Updated to specify interaction with new language features, like full > variance and property types. > * Updated for the use of the ?Type syntax rather than the Type|null > syntax. > * Only supports "false" as a pseudo-type, not "true". > * Slightly simplified semantics for the coercive typing mode. > > Regards, > Nikita > An implementation of this proposal is now available at https://github.com/php/php-src/pull/4838. As the implementation didn't turn up any new issues, I think it's time to move this RFC forward to voting. Nikita CAUTION: This email originated from outside of the organization. Do not click on links or open attachments unless you recognize the sender and know the content is safe.
