Nice! I've read the RFC and there's only one missing thing that is either undocumented or missed during patch creation: instanceof. I'd be amazing if we could do: $foo instanceof Foo & Bar
Cheers, On Thu, Apr 28, 2016 at 5:00 AM, Josh Di Fabio <joshdifa...@gmail.com> wrote: > On Thu, Apr 28, 2016 at 4:54 AM, Levi Morrison <le...@php.net> wrote: > > Internals, > > > > As alluded to last week I have another RFC for improving the type > > system: [intersection types][1]. > > > > It allows parameters to define multiple type constraints that must be > > satisfied. Common combinations of our built-in types include > > `ArrayAccess & Traversable & Countable` and `Countable & Iterator`. > > > > Some people have suggest I merge this and union types into one RFC. > > For now I'll just proceed with them separately to gain feedback. > > > > [1]: http://wiki.php.net/rfc/intersection_types > > > > -- > > PHP Internals - PHP Runtime Development Mailing List > > To unsubscribe, visit: http://www.php.net/unsub.php > > > > To me, it seems that intersection types are more useful than union > types (other than the obvious null|Foo and array|Traversable cases) as > they'd allow us to write smaller interfaces and better follow ISP in > userland, with interfaces becoming much more convenient for > documenting the requirements of a parameter. > > At present we tend to have incomplete implementations of interfaces > (e.g. throw OperationNotSupportedException). Union types would allow > us to create more, smaller interfaces and avoid situations where the > type of a parameter doesn't accurately reflect the method's true > requirements, or where concretions are incomplete implementations of > an interface. > > Thanks for your efforts, Levi, I'm excited about this one! > > -- > PHP Internals - PHP Runtime Development Mailing List > To unsubscribe, visit: http://www.php.net/unsub.php > > -- Guilherme Blanco Lead Architect at E-Block
