Sent from my iPhone
> On Sep 13, 2017, at 11:56 AM, David Zarzycki via swift-dev > <swift-dev@swift.org> wrote: > > > >> On Sep 13, 2017, at 13:53, David Sweeris <daveswee...@mac.com> wrote: >> >> >>> On Sep 13, 2017, at 09:54, David Zarzycki via swift-dev >>> <swift-dev@swift.org> wrote: >>> >>> Hello, >>> >>> As a part of a research project that I’m working on, I’ve started bumping >>> into the need for value-type bound protocols (as opposed to the existing >>> class bound protocols). Is this something that would be worth proposing >>> formally? Or should I just keep the patch I have on my research branch? >> >> I think it'd be worth a proposal, especially if can talk about why you >> needed it. > > While I look forward to talking about my research, I’m not ready to do in the > near future. > > That being said, value-type bound protocols seem independently useful and > that is why I emailed the list. > > I think the use case for this is generic algorithms. Why? Because it can be > hard to impossible to write *robust* generic code when you don’t know whether > an abstract type copies by value or by reference during > assignment/initialization. With class-bound protocols, you can guarantee > reference semantics, but there is no analogous feature for ensuring value > semantics. I have a small (~150 line) patch that fixes this. Value types and value semantics are not the same. Most people who have asked for this capability actually want a constraint for value semantics, not value types. Is that what you're asking for as well? > > Dave > _______________________________________________ > swift-dev mailing list > swift-dev@swift.org > https://lists.swift.org/mailman/listinfo/swift-dev _______________________________________________ swift-dev mailing list swift-dev@swift.org https://lists.swift.org/mailman/listinfo/swift-dev
