<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><br class=""><div><blockquote type="cite" class=""><div class="">On Sep 10, 2016, at 5:25 PM, Charles Srstka <<a href="mailto:cocoadev@charlessoft.com" class="">cocoadev@charlessoft.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><meta http-equiv="Content-Type" content="text/html charset=us-ascii" class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><blockquote type="cite" class="">On Sep 10, 2016, at 2:52 PM, Xiaodi Wu via swift-evolution <<a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a>> wrote:<br class=""></blockquote><div class=""><blockquote type="cite" class=""><br class="Apple-interchange-newline"><div class=""><span 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;" class="">Is that (i.e. having properties in extensions) listed in the completing generics manifesto? It certainly seems like it'd be a worthwhile feature to consider under that umbrella.</span></div></blockquote></div><br class=""><div class="">I think that came up at some point, but was deemed not to be implementable in a sufficiently performant way.</div></div></div></blockquote><br class=""></div><div>It seems like it ought to be implementable for _in-module_ extensions, since presumably the memory layout of each type is fungible until the module is compiled.</div><div><br class=""></div><div>In-module extensions address the use case I had in mind, namely breaking apart a large type by isolating some private properties within extensions. It seems like the possible and the desirable may actually intersect here.</div><div><br class=""></div><div>P</div><br class=""></body></html>