[swift-evolution] [Review] SE-0065 A New Model for Collections and Indices

Dave Abrahams dabrahams at apple.com
Mon Apr 11 15:03:38 CDT 2016

on Mon Apr 11 2016, Joe Groff <swift-evolution at swift.org> wrote:

>> • Because Swift is unable to express conditional protocol
> conformances, implementing this change has required us to create a
> great deal of complexity in the standard library API. Aside from the
> two excess “Countable” range types, there are new overloads for
> slicing and twelve distinct slice types that capture all the
> combinations of traversal, mutability, and range-replaceability. While
> these costs are probably temporary, they are very real in the
> meantime.
> Is there a migration strategy possible for when we do support
> conditional conformances? 

Anything is possible ;-)

> Would typealiasing the existing names to refinements of a more general
> Slice<T> type be sufficient?

Maybe.  It depends on your goals.  *Some* code will break no matter what
we do.


More information about the swift-evolution mailing list