<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><br class=""><div><br class=""><blockquote type="cite" class=""><div class="">On Nov 21, 2017, at 10:37 PM, Chris Lattner <<a href="mailto:clattner@nondot.org" class="">clattner@nondot.org</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><meta http-equiv="Content-Type" content="text/html; charset=utf-8" class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">On Nov 21, 2017, at 9:25 PM, Douglas Gregor <<a href="mailto:dgregor@apple.com" class="">dgregor@apple.com</a>> wrote:<br class=""><div class=""><blockquote type="cite" class=""><div class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div class=""><blockquote type="cite" class=""><div class=""><div style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class="">Or alternatively, one could decide to make the generics system *only and forever* work on nominal types, and make the syntactic sugar just be sugar for named types like Swift.Tuple, Function, and Optional. Either design could work.</div></div></blockquote><br class=""></div><div class="">We don’t have a way to make it work for function types, though, because of parameter-passing conventions. Well, assuming we don’t invent something that allows:</div><div class=""><br class=""></div><div class=""><span class="Apple-tab-span" style="white-space:pre"> </span>Function<Double, inout String></div><div class=""><br class=""></div><div class="">to exist in the type system. Tuple labels have a similar problem.</div></div></div></blockquote><br class=""></div><div class="">I’m totally aware of that and mentioned it upthread. </div></div></div></blockquote><div><br class=""></div><div>Eh, sorry I missed it.</div><br class=""><blockquote type="cite" class=""><div class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div class=""> There are various encoding tricks that could make this work depending on how you want to stretch the current generics system…</div></div></div></blockquote><br class=""></div><div>I think it’s straightforward and less ugly to make structural types allow extensions and protocol conformances.</div><div><br class=""></div><div><span class="Apple-tab-span" style="white-space:pre"> </span>- Doug</div><div><br class=""></div><br class=""></body></html>