> On May 4, 2016, at 4:16 PM, David Sweeris <[email protected]> wrote: > > Having given it some more thought... Does "PureReference" make sense? What > would it mean? At some point a reference has to, you know, actually refer to > a concrete value. Otherwise it's just turtles all the way down.
In my thinking PureReference (or ImmutableObject) has semantics indicating that the type is a value-semantic reference type. I think this could be quite useful in some cases. > > Sent from my iPhone > >> On May 4, 2016, at 13:32, Matthew Johnson <[email protected]> wrote: >> >> >>> On May 4, 2016, at 1:21 PM, David Sweeris via swift-evolution >>> <[email protected]> wrote: >>> >>> >>>> On May 4, 2016, at 11:12, Joe Groff via swift-evolution >>>> <[email protected]> wrote: >>>> >>>> I can see value in there being some kind of PureValue protocol, for types >>>> that represent fully self-contained values, but conforming to that >>>> protocol requires a bit more thought than just being a struct or enum, >>>> since there are structs that have reference semantics (such as >>>> UnsafePointer), and there are hybrid value types that contain references >>>> to data that isn't part of the value (an Array<Class>, for instance). >>>> >>>> -Joe >>> >>> +1 >>> >>> I'd think that both "PureValue" and "PureReference" would be useful. Isn't >>> it the mixed types that make for tricky mutation rules & serialization? >> >> I also like Joe’s idea. It fits with the direction in Swift of attaching >> semantics, not just syntax, to protocols. >> >> I was thinking of something pretty similar to your PureReference idea, but >> slightly different. Pure / immutable references have value semantics. With >> that in mind I was thinking of an ImmutableObject protocol which would >> inherit from both AnyObject and PureValue. >> >> >>> _______________________________________________ >>> swift-evolution mailing list >>> [email protected] >>> https://lists.swift.org/mailman/listinfo/swift-evolution >> _______________________________________________ swift-evolution mailing list [email protected] https://lists.swift.org/mailman/listinfo/swift-evolution
