Re: [RFC] Enumerations

On Fri, Dec 4, 2020, at 5:24 PM, Larry Garfield wrote: > Greetings, denizens of Internals! > > Ilija Tovilo and I have been working for the last few months on adding > support for enumerations and algebraic data types to PHP. This is a > not-small task, so we've broken it up into several stages. The first > stage, unit enumerations, are just about ready for public review and > discussion. > > The overarching plan (for context, NOT the thing to comment on right > now) is here: https://wiki.php.net/rfc/adts > > The first step, for unit enumerations, is here: > > https://wiki.php.net/rfc/enumerations > > There's still a few bits we're sorting out and the implementation is > mostly done, but not 100% complete. Still, it's far enough along to > start a discussion on and get broader feedback on the outstanding nits. > > I should note that while the design has been collaborative, credit for > the implementation goes entirely to Ilija. Blame for any typos in the > RFC itself go entirely to me. > > *dons flame-retardant suit* > > -- > Larry Garfield > larry@garfieldtech.com Thank you everyone for the feedback so far! I've updated the RFC with a few changes, based on discussion here and elsewhere: * Clarified that "enums behave like objects unless otherwise specified." That should clarify a lot of edge case questions. (Which is specifically one of the reasons to build off of objects. We can inherit answers to most edge cases.) * Primitive-backed Cases have been renamed to Scalar Enums, because "Primitive-backed" is just too clumsy to say or write all the time. * There's now formal internal interfaces defined for Enum, UnitEnum, and ScalarEnum to define the methods mentioned. These serve as both documentation and to allow user-space code to tell when a value it's dealing with is an enum, and a particular type of enum. (And therefore what enum methods are available.) * Added a value() method to ScalarEnum, to make it easier to get at the scalar equivalent arbitrarily. * Fixed a bunch of typos. * Updated the reflection section to have getType() return a ReflectionType rather than a bare string. (The patch will be updated for the above shortly as Ilija's time allows.) --Larry Garfield