<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><div><br><br>Sent from my iPad</div><div><br>On May 27, 2016, at 11:07 AM, Thorsten Seitz <<a href="mailto:tseitz42@icloud.com">tseitz42@icloud.com</a>> wrote:<br><br></div><blockquote type="cite"><div><meta http-equiv="Content-Type" content="text/html charset=utf-8"><br class=""><div><blockquote type="cite" class=""><div class="">Am 27.05.2016 um 16:54 schrieb Matthew Johnson <<a href="mailto:matthew@anandabits.com" class="">matthew@anandabits.com</a>>:</div><br class="Apple-interchange-newline"><div class=""><blockquote type="cite" class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><div class=""><br class="Apple-interchange-newline">On May 27, 2016, at 8:18 AM, Thorsten Seitz via swift-evolution <<a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="" style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">Personally I think `&` is more lightweight (and it is established in other languages like Ceylon and Typescript) and `where` is more expressive (and established in Swift for introducing constraints), so I would stay with these.</div></div></blockquote><div style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><br class=""></div><div style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class="">I agree. If we can make `&` with `where` work syntactically it would be nice to go in this lighter weight direction. If we decide to do that the question then becomes what to do with `protocol`. Would it be feasible to replace it with `&` in Swift 3 if we decide on that direction?</div></div></blockquote><div><br class=""></div>Yep. `protocol` should be replaced with `&` in that case.</div></div></blockquote><div><br></div>Right, but it's a much larger syntax change. If we decide on that direction and it's not feasible for Swift 3 I suppose we would just leave 'protocol' alone until Swift 3.x or 4.<div><br><blockquote type="cite"><div><div><br class=""></div><div>-Thorsten</div><div><br class=""></div><div><br class=""><blockquote type="cite" class=""><div class=""><br class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><blockquote type="cite" class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><div class=""><div class="" style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div class=""><br class=""></div><div class="">-Thorsten<br class=""><div class=""><br class=""></div><div class=""><br class=""><div class=""><blockquote type="cite" class=""><div class="">Am 27.05.2016 um 14:34 schrieb Vladimir.S <<a href="mailto:svabox@gmail.com" class="">svabox@gmail.com</a>>:</div><br class="Apple-interchange-newline"><div class=""><span class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;">Btw, in case we have `where` keyword in syntax related to types/protocols (when defining constrains. and not some symbol like '>>'.. don't know, for example), why we can't have 'and' keyword also when discuss the syntax of type/protocol conjunction?</span><br class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><span class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;">I.e.</span><br class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><br class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><span class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;">let x: P and Q</span><br class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><span class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;">let x: P and Q where P.T == Q.T</span><br class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><span class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;">let x: P and Q and R</span><br class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><br class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><span class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;">or, for consistency, as I understand it, we should have</span><br class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><span class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;">let x: P & Q >> P.T == Q.T</span><br class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><br class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><span class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;">On 27.05.2016 11:55, Thorsten Seitz via swift-evolution wrote:</span><br class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><blockquote type="cite" class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;">We could just write<br class=""><br class="">let x: P & Q<br class="">instead of<br class="">let x: Any<P, Q><br class=""><br class="">let x: Collection where .Element: P<br class="">instead of<br class="">let x: Any<Collection where .Element: P><br class=""><br class="">let x: P & Q where P.T == Q.T<br class="">instead of<br class="">let x: Any<P, Q where P.T == Q.T><br class=""><br class="">let x: P & Q & R<br class="">instead of<br class="">let x: Any<P, Q, R><br class=""><br class="">let x: Collection<br class="">instead of<br class="">let x: Any<Collection><br class=""><br class=""><br class="">This would avoid the confusion of Any<T1, T2> being something completely<br class="">different than a generic type (i.e. order of T1, T2 does not matter whereas<br class="">for generic types it is essential).<br class=""><br class=""><br class="">-Thorsten<br class=""><br class=""><br class=""><br class=""><blockquote type="cite" class="">Am 26.05.2016 um 20:11 schrieb Adrian Zubarev via swift-evolution<br class=""><<a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a><span class="Apple-converted-space"> </span><<a href="mailto:swift-evolution@swift.org" class="">mailto:swift-evolution@swift.org</a>>>:<br class=""><br class="">Something like |type<…>| was considered at the very start of the whole<br class="">discussion (in this thread<br class=""><<a href="https://lists.swift.org/pipermail/swift-evolution/Week-of-Mon-20160502/016523.html" class="">https://lists.swift.org/pipermail/swift-evolution/Week-of-Mon-20160502/016523.html</a>>),<br class="">but it does not solve the meaning of an existential type and also might<br class="">lead to even more confusion.<br class=""><br class="">From my perspective I wouldn’t use parentheses here because it looks more<br class="">like an init without any label |Type.init(…)| or |Type(…)|. I could live<br class="">with |Any[…]| but this doesn’t look shiny and Swifty to me. Thats only my<br class="">personal view. ;)<br class=""><br class=""><br class=""><br class=""><br class="">--<br class="">Adrian Zubarev<br class="">Sent with Airmail<br class=""><br class="">Am 26. Mai 2016 bei 19:48:04, Vladimir.S via swift-evolution<br class="">(<a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a><span class="Apple-converted-space"> </span><<a href="mailto:swift-evolution@swift.org" class="">mailto:swift-evolution@swift.org</a>>) schrieb:<br class=""><br class=""><blockquote type="cite" class="">Don't think {} is better here, as they also have "established meaning in<br class="">Swift today".<br class=""><br class="">How about just Type(P1 & P2 | P3) - as IMO we can think of such<br class="">construction as "creation" of new type and `P1 & P2 | P3` could be treated<br class="">as parameters to initializer.<br class=""><br class="">func f(t: Type(P1 & P2 | P3)) {..}<br class=""><br class=""><br class="">On 26.05.2016 20:32, L. Mihalkovic via swift-evolution wrote:<br class="">> How about something like Type{P1 & P2 | P3} the point being that "<...>" has an established meaning in Swift today which is not what is expressed in the "<P1,P2,P3>" contained inside Any<P1, P2,P3>.<br class="">><br class="">>> On May 26, 2016, at 7:11 PM, Dave Abrahams via swift-evolution <<a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a><span class="Apple-converted-space"> </span><<a href="mailto:swift-evolution@swift.org" class="">mailto:swift-evolution@swift.org</a>>> wrote:<br class="">>><br class="">>><br class="">>>> on Thu May 26 2016, Adrian Zubarev <<a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a><span class="Apple-converted-space"> </span><<a href="mailto:swift-evolution@swift.org" class="">mailto:swift-evolution@swift.org</a>>> wrote:<br class="">>>><br class="">>>> There is great feedback going on here. I'd like to consider a few things here:<br class="">>>><br class="">>>> * What if we name the whole thing `Existential<>` to sort out all<br class="">>>> confusion?<br class="">>><br class="">>> Some of us believe that “existential” is way too theoretical a word to<br class="">>> force into the official lexicon of Swift. I think “Any<...>” is much<br class="">>> more conceptually accessible.<br class="">>><br class="">>>><br class="">>>> This would allow `typealias Any = Existential<>`. * Should<br class="">>>> `protocol A: Any<class>` replace `protocol A: class`? Or at least<br class="">>>> deprecate it. * Do we need `typealias AnyClass = Any<class>` or do we<br class="">>>> want to use any class requirement existential directly? If second, we<br class="">>>> will need to allow direct existential usage on protocols (right now we<br class="">>>> only can use typealiases as a worksround).<br class="">>><br class="">>> --<br class="">>> Dave<br class="">>><br class="">>> _______________________________________________<br class="">>> swift-evolution mailing list<br class="">>><span class="Apple-converted-space"> </span><a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a><span class="Apple-converted-space"> </span><<a href="mailto:swift-evolution@swift.org" class="">mailto:swift-evolution@swift.org</a>><br class="">>><span class="Apple-converted-space"> </span><a href="https://lists.swift.org/mailman/listinfo/swift-evolution" class="">https://lists.swift.org/mailman/listinfo/swift-evolution</a><br class="">> _______________________________________________<br class="">> swift-evolution mailing list<br class="">><span class="Apple-converted-space"> </span><a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a><span class="Apple-converted-space"> </span><<a href="mailto:swift-evolution@swift.org" class="">mailto:swift-evolution@swift.org</a>><br class="">><span class="Apple-converted-space"> </span><a href="https://lists.swift.org/mailman/listinfo/swift-evolution" class="">https://lists.swift.org/mailman/listinfo/swift-evolution</a><br class="">><br class="">_______________________________________________<br class="">swift-evolution mailing list<br class=""><a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a><span class="Apple-converted-space"> </span><<a href="mailto:swift-evolution@swift.org" class="">mailto:swift-evolution@swift.org</a>><br class=""><a href="https://lists.swift.org/mailman/listinfo/swift-evolution" class="">https://lists.swift.org/mailman/listinfo/swift-evolution</a><br class=""></blockquote><br class="">_______________________________________________<br class="">swift-evolution mailing list<br class=""><a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a><span class="Apple-converted-space"> </span><<a href="mailto:swift-evolution@swift.org" class="">mailto:swift-evolution@swift.org</a>><br class=""><a href="https://lists.swift.org/mailman/listinfo/swift-evolution" class="">https://lists.swift.org/mailman/listinfo/swift-evolution</a><br class=""></blockquote><br class=""><br class=""><br class="">_______________________________________________<br class="">swift-evolution mailing list<br class=""><a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a><br class=""><a href="https://lists.swift.org/mailman/listinfo/swift-evolution" class="">https://lists.swift.org/mailman/listinfo/swift-evolution</a></blockquote></div></blockquote></div><br class=""></div></div></div>_______________________________________________<br class="">swift-evolution mailing list<br class=""><a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a><br class=""><a href="https://lists.swift.org/mailman/listinfo/swift-evolution" class="">https://lists.swift.org/mailman/listinfo/swift-evolution</a></div></blockquote></div></blockquote></div><br class=""></div></blockquote></div></body></html>