On Sat, Jul 4, 2015 at 9:31 AM, Trevor Suarez <ric...@gmail.com> wrote:
> > On Fri, Jul 3, 2015 at 12:24 PM Nikita Popov <nikita....@gmail.com> wrote: > >> Hi internals! >> >> In a previous thread on the topic [1] I promised to create an RFC for the >> soft-reservation of 'void', similar to a bunch of other reservations we >> have done for PHP 7. The RFC also includes 'enum' as an additional >> independent proposal, as I think this will likely be needed in 7.x. If you >> have further suggestions for names or keywords that we are likely to need, >> please point them out. >> >> https://wiki.php.net/rfc/additional_soft_reservations_for_php7 >> >> Thanks, >> Nikita >> >> [1]: http://markmail.org/message/ovvnz5p2o6q7ebjl > > > Yea, this is smart to get this going. I think it makes a lot of sense. I'd > love to see "struct" added to this list, so we could potentially add a > value object structure of some sort down the road. > > As far as "prior art", you can see that there's already some interest in > this area: > > - https://twitter.com/auroraeosrose/status/616321058904350720 > - https://gist.github.com/auroraeosrose/2036d1d675a4bd254450 > - https://gist.github.com/Antnee/237334e1eb937892ad7a > > Anyway, yea. Makes sense to me. 👍 > So there are two questions to answer here: a) How likely is it that this will be implemented in the near future? I've added "enum" to the list, because there is already an existing proposal, which I personally consider relatively likely to pass. Structs are as-yet a vague concept and may be implemented in very different ways. As far as I see the only fundamental difference between a "struct" and a "class" per the above definition is that you can't create dynamic properties on it - which is something that can be solved from a different angle as well (declare strict mode). b) Do we really need a keyword to implement this feature? For example, instead of "struct Foo {}" we could use the syntax "struct class Foo {}", in which case the new "keyword" would be "struct class" and we do not cause BC issues. Note that this also applies to "enum" where we could use "enum class Foo {}" instead. This syntax has precedent in C++11. Thinking about this now, this might be a better option, because there's a lot of code using "enum" in name segments [1] (it's pretty much the natural choice for userland enum implementations...) and introducing this keyword might result in a non-trivial amount of breakage (cc Levi). "struct" looks less problematic [2]. Nikita [1]: https://github.com/search?l=PHP&p=1&q=enum&type=Code&utf8=%E2%9C%93 [2]: https://github.com/search?l=php&q=struct&ref=searchresults&type=Code&utf8=%E2%9C%93
