> On Jul 29, 2017, at 4:33 PM, Chris Lattner <[email protected]> wrote: >> On Jul 29, 2017, at 1:32 PM, John McCall <[email protected]> wrote: >> >>> On Jul 29, 2017, at 4:24 PM, Chris Lattner via swift-dev >>> <[email protected]> wrote: >>> >>> On Jul 28, 2017, at 2:20 PM, Joe Groff via swift-dev <[email protected]> >>> wrote: >>>> >>>> Overall, my intuition is that the tradeoffs come out in favor for >>>> nonunique metadata objects, but what do you all think? Is there anything >>>> I'm missing? >>> >>> I think your proposal makes sense, particularly when we start caring about >>> metadata/conformances for non-nominal types, which don’t have a declaration >>> location. They are a bit over the horizon right now, but we need to >>> support making tuples conform to protocols someday. Eliminating the >>> requirement for them to be uniquely emitted across the entire program would >>> make that much simpler, because otherwise you’re in the land of weak >>> symbols or something. >> >> Not really, because the conformance is presumably still declared somewhere >> in Swift and therefore has a natural unique definition point even if the >> type doesn’t. > > Ok, so you’re suggesting that the stdlib would have the “automatically > provided” conditional conformances for things like equatable, then each > module that actually uses one gets a specialization?
Well, presumably the stdlib's generic conformance would actually be usable itself, but yes, other modules could of course emit specialized witness tables if they want. John. _______________________________________________ swift-dev mailing list [email protected] https://lists.swift.org/mailman/listinfo/swift-dev
